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# Source code for xonsh.procs.proxies

    """Interface for running Python functions as subprocess-mode commands.

    Code for several helper methods in the `ProcProxy` class have been reproduced
    without modification from `subprocess.py` in the Python 3.4.2 standard library.
    The contents of `subprocess.py` (and, thus, the reproduced methods) are
    Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se> and were
    licensed to the Python Software foundation under a Contributor Agreement.
    """

    import collections.abc as cabc
    import io
    import os
    import signal
    import subprocess
    import sys
    import threading
    import time

    import xonsh.lib.lazyimps as xli
    import xonsh.platform as xp
    import xonsh.tools as xt
    from xonsh.built_ins import XSH
    from xonsh.cli_utils import run_with_partial_args
    from xonsh.procs.readers import safe_fdclose

    def still_writable(fd):
        """Determines whether a file descriptor is still writable by trying to
        write an empty string and seeing if it fails.
        """
        try:
            os.write(fd, b"")
            status = True
        except OSError:
            status = False
        return status

    def safe_flush(handle):
        """Attempts to safely flush a file handle, returns success bool."""
        status = True
        try:
            handle.flush()
        except OSError:
            status = False
        return status

    class Handle(int):
        closed = False

        def Close(self, CloseHandle=None):
            CloseHandle = CloseHandle or xli._winapi.CloseHandle
            if not self.closed:
                self.closed = True
                CloseHandle(self)

        def Detach(self):
            if not self.closed:
                self.closed = True
                return int(self)
            raise ValueError("already closed")

        def __repr__(self):
            return f"Handle({int(self)})"

        __del__ = Close
        __str__ = __repr__

    class FileThreadDispatcher:
        """Dispatches to different file handles depending on the
        current thread. Useful if you want file operation to go to different
        places for different threads.
        """

        def __init__(self, default=None):
            """
            Parameters
            ----------
            default : file-like or None, optional
                The file handle to write to if a thread cannot be found in
                the registry. If None, a new in-memory instance.

            Attributes
            ----------
            registry : dict
                Maps thread idents to file handles.
            """
            if default is None:
                default = io.TextIOWrapper(io.BytesIO())
            self.default = default
            self.registry = {}

        def register(self, handle):
            """Registers a file handle for the current thread. Returns self so
            that this method can be used in a with-statement.
            """
            if handle is self:
                # prevent weird recurssion errors
                return self
            self.registry[threading.get_ident()] = handle
            return self

        def deregister(self):
            """Removes the current thread from the registry."""
            ident = threading.get_ident()
            if ident in self.registry:
                # don't remove if we have already been deregistered
                del self.registry[threading.get_ident()]

        @property
        def available(self):
            """True if the thread is available in the registry."""
            return threading.get_ident() in self.registry

        @property
        def handle(self):
            """Gets the current handle for the thread."""
            return self.registry.get(threading.get_ident(), self.default)

        def __enter__(self):
            pass

        def __exit__(self, ex_type, ex_value, ex_traceback):
            self.deregister()

        #
        # io.TextIOBase interface
        #

        @property
        def encoding(self):
            """Gets the encoding for this thread's handle."""
            return self.handle.encoding

        @property
        def errors(self):
            """Gets the errors for this thread's handle."""
            return self.handle.errors

        @property
        def newlines(self):
            """Gets the newlines for this thread's handle."""
            return self.handle.newlines

        @property
        def buffer(self):
            """Gets the buffer for this thread's handle."""
            return self.handle.buffer

        def detach(self):
            """Detaches the buffer for the current thread."""
            return self.handle.detach()

        def read(self, size=None):
            """Reads from the handle for the current thread."""
            return self.handle.read(size)

        def readline(self, size=-1):
            """Reads a line from the handle for the current thread."""
            return self.handle.readline(size)

        def readlines(self, hint=-1):
            """Reads lines from the handle for the current thread."""
            return self.handle.readlines(hint)

        def seek(self, offset, whence=io.SEEK_SET):
            """Seeks the current file."""
            return self.handle.seek(offset, whence)

        def tell(self):
            """Reports the current position in the handle for the current thread."""
            return self.handle.tell()

        def write(self, s):
            """Writes to this thread's handle. This also flushes, just to be
            extra sure the string was written.
            """
            h = self.handle
            try:
                r = h.write(s)
                h.flush()
            except OSError:
                r = None
            return r

        @property
        def line_buffering(self):
            """Gets if line buffering for this thread's handle enabled."""
            return self.handle.line_buffering

        #
        # io.IOBase interface
        #

        def close(self):
            """Closes the current thread's handle."""
            return self.handle.close()

        @property
        def closed(self):
            """Is the thread's handle closed."""
            return self.handle.closed

        def fileno(self):
            """Returns the file descriptor for the current thread."""
            return self.handle.fileno()

        def flush(self):
            """Flushes the file descriptor for the current thread."""
            return safe_flush(self.handle)

        def isatty(self):
            """Returns if the file descriptor for the current thread is a tty."""
            if self.default:
                return self.default.isatty()
            return self.handle.isatty()

        def readable(self):
            """Returns if file descriptor for the current thread is readable."""
            return self.handle.readable()

        def seekable(self):
            """Returns if file descriptor for the current thread is seekable."""
            return self.handle.seekable()

        def truncate(self, size=None):
            """Truncates the file for for the current thread."""
            return self.handle.truncate()

        def writable(self, size=None):
            """Returns if file descriptor for the current thread is writable."""
            return self.handle.writable(size)

        def writelines(self):
            """Writes lines for the file descriptor for the current thread."""
            return self.handle.writelines()

    # These should NOT be lazy since they *need* to get the true stdout from the
    # main thread. Also their creation time should be negligible.
    STDOUT_DISPATCHER = FileThreadDispatcher(default=sys.stdout)
    STDERR_DISPATCHER = FileThreadDispatcher(default=sys.stderr)

    def parse_proxy_return(r, stdout, stderr):
        """Proxies may return a variety of outputs. This handles them generally.

        Parameters
        ----------
        r : tuple, str, int, or None
            Return from proxy function
        stdout : file-like
            Current stdout stream
        stdout : file-like
            Current stderr stream

        Returns
        -------
        cmd_result : int
            The return code of the proxy
        """
        cmd_result = 0
        if isinstance(r, str):
            stdout.write(r)
            stdout.flush()
        elif isinstance(r, int):
            cmd_result = r
        elif isinstance(r, cabc.Sequence):
            rlen = len(r)
            if rlen > 0 and r[0] is not None:
                stdout.write(str(r[0]))
                stdout.flush()
            if rlen > 1 and r[1] is not None:
                stderr.write(xt.endswith_newline(str(r[1])))
                stderr.flush()
            if rlen > 2 and isinstance(r[2], int):
                cmd_result = r[2]
        elif r is not None:
            # for the random object...
            stdout.write(str(r))
            stdout.flush()
        return cmd_result

    def get_proc_proxy_name(cls):
        return repr(
            {
                "cls": cls.__class__.__name__,
                "name": getattr(cls, "name", None),
                "func": cls.f,
                "alias": cls.env.get("__ALIAS_NAME", None),
                "pid": cls.pid,
            }
        )

    class ProcProxyThread(threading.Thread):
        """
        Class representing a function to be run as a subprocess-mode command.
        """

        def __init__(
            self,
            f,
            args,
            stdin=None,
            stdout=None,
            stderr=None,
            universal_newlines=False,
            close_fds=False,
            env=None,
        ):
            """Parameters
            ----------
            f : function
                The function to be executed.
            args : list
                A (possibly empty) list containing the arguments that were given on
                the command line
            stdin : file-like, optional
                A file-like object representing stdin (input can be read from
                here).  If `stdin` is not provided or if it is explicitly set to
                `None`, then an instance of `io.StringIO` representing an empty
                file is used.
            stdout : file-like, optional
                A file-like object representing stdout (normal output can be
                written here).  If `stdout` is not provided or if it is explicitly
                set to `None`, then `sys.stdout` is used.
            stderr : file-like, optional
                A file-like object representing stderr (error output can be
                written here).  If `stderr` is not provided or if it is explicitly
                set to `None`, then `sys.stderr` is used.
            universal_newlines : bool, optional
                Whether or not to use universal newlines.
            close_fds : bool, optional
                Whether or not to close file descriptors. This is here for Popen
                compatability and currently does nothing.
            env : Mapping, optional
                Environment mapping.
            """
            self.f = f
            self.args = args
            self.pid = None
            self.returncode = None
            self._closed_handle_cache = {}

            handles = self._get_handles(stdin, stdout, stderr)
            (
                self.p2cread,
                self.p2cwrite,
                self.c2pread,
                self.c2pwrite,
                self.errread,
                self.errwrite,
            ) = handles

            # default values
            self.stdin = stdin
            self.stdout = stdout
            self.stderr = stderr
            self.close_fds = close_fds
            self.env = env
            self._interrupted = False

            if xp.ON_WINDOWS:
                if self.p2cwrite != -1:
                    self.p2cwrite = xli.msvcrt.open_osfhandle(self.p2cwrite.Detach(), 0)
                if self.c2pread != -1:
                    self.c2pread = xli.msvcrt.open_osfhandle(self.c2pread.Detach(), 0)
                if self.errread != -1:
                    self.errread = xli.msvcrt.open_osfhandle(self.errread.Detach(), 0)

            if self.p2cwrite != -1:
                self.stdin = open(self.p2cwrite, "wb", -1)
                if universal_newlines:
                    self.stdin = io.TextIOWrapper(
                        self.stdin, write_through=True, line_buffering=False
                    )
            elif isinstance(stdin, int) and stdin != 0:
                self.stdin = open(stdin, "wb", -1)

            if self.c2pread != -1:
                self.stdout = open(self.c2pread, "rb", -1)
                if universal_newlines:
                    self.stdout = io.TextIOWrapper(self.stdout)

            if self.errread != -1:
                self.stderr = open(self.errread, "rb", -1)
                if universal_newlines:
                    self.stderr = io.TextIOWrapper(self.stderr)

            # Set some signal handles, if we can. Must come before process
            # is started to prevent deadlock on windows
            self.old_int_handler = None
            if xt.on_main_thread():
                self.old_int_handler = signal.signal(signal.SIGINT, self._signal_int)
            # start up the proc
            super().__init__()
            # This is so the thread will use the same swapped values as the origin one.
            self.original_swapped_values = XSH.env.get_swapped_values()
            self.start()

        def __del__(self):
            self._restore_sigint()

        def run(self):
            """Set up input/output streams and execute the child function in a new
            thread.  This is part of the `threading.Thread` interface and should
            not be called directly.
            """
            if self.f is None:
                return
            # Set the thread-local swapped values.
            XSH.env.set_swapped_values(self.original_swapped_values)
            spec = self._wait_and_getattr("spec")
            last_in_pipeline = spec.last_in_pipeline
            if last_in_pipeline:
                capout = spec.captured_stdout  # NOQA
                caperr = spec.captured_stderr  # NOQA
            env = XSH.env
            enc = env.get("XONSH_ENCODING")
            err = env.get("XONSH_ENCODING_ERRORS")
            if xp.ON_WINDOWS:
                if self.p2cread != -1:
                    self.p2cread = xli.msvcrt.open_osfhandle(self.p2cread.Detach(), 0)
                if self.c2pwrite != -1:
                    self.c2pwrite = xli.msvcrt.open_osfhandle(self.c2pwrite.Detach(), 0)
                if self.errwrite != -1:
                    self.errwrite = xli.msvcrt.open_osfhandle(self.errwrite.Detach(), 0)
            # get stdin
            if self.stdin is None:
                sp_stdin = None
            elif self.p2cread != -1:
                sp_stdin = io.TextIOWrapper(
                    open(self.p2cread, "rb", -1), encoding=enc, errors=err
                )
            else:
                sp_stdin = sys.stdin
            # stdout
            if self.c2pwrite != -1:
                sp_stdout = io.TextIOWrapper(
                    open(self.c2pwrite, "wb", -1), encoding=enc, errors=err
                )
            else:
                sp_stdout = sys.stdout
            # stderr
            if self.errwrite == self.c2pwrite:
                sp_stderr = sp_stdout
            elif self.errwrite != -1:
                sp_stderr = io.TextIOWrapper(
                    open(self.errwrite, "wb", -1), encoding=enc, errors=err
                )
            else:
                sp_stderr = sys.stderr
            # run the function itself
            try:
                alias_stack = XSH.env.get("__ALIAS_STACK", "")
                if self.env and self.env.get("__ALIAS_NAME"):
                    alias_stack += ":" + self.env["__ALIAS_NAME"]

                with (
                    STDOUT_DISPATCHER.register(sp_stdout),
                    STDERR_DISPATCHER.register(sp_stderr),
                    xt.redirect_stdout(STDOUT_DISPATCHER),
                    xt.redirect_stderr(STDERR_DISPATCHER),
                    XSH.env.swap(self.env, __ALIAS_STACK=alias_stack),
                ):
                    r = run_with_partial_args(
                        self.f,
                        {
                            "args": self.args,
                            "stdin": sp_stdin,
                            "stdout": sp_stdout,
                            "stderr": sp_stderr,
                            "spec": spec,
                            "stack": spec.stack,
                        },
                    )
            except SystemExit as e:
                r = e.code if isinstance(e.code, int) else int(bool(e.code))
            except OSError:
                status = still_writable(self.c2pwrite) and still_writable(self.errwrite)
                if status:
                    # stdout and stderr are still writable, so error must
                    # come from function itself.
                    xt.print_exception(
                        source_msg="Exception in thread " + get_proc_proxy_name(self)
                    )
                    r = 1
                else:
                    # stdout and stderr are no longer writable, so error must
                    # come from the fact that the next process in the pipeline
                    # has closed the other side of the pipe. The function then
                    # attempted to write to this side of the pipe anyway. This
                    # is not truly an error and we should exit gracefully.
                    r = 0
            except Exception:
                xt.print_exception(
                    source_msg="Exception in thread " + get_proc_proxy_name(self)
                )
                r = 1
            safe_flush(sp_stdout)
            safe_flush(sp_stderr)
            self.returncode = parse_proxy_return(r, sp_stdout, sp_stderr)
            if not last_in_pipeline and not xp.ON_WINDOWS:
                # mac requires us *not to* close the handles here while
                # windows requires us *to* close the handles here
                return
            # clean up
            # scopz: not sure why this is needed, but stdin cannot go here
            # and stdout & stderr must.
            if xp.ON_WINDOWS:
                handles = [self.stdout, self.stderr]
            else:
                handles = [sp_stdout, sp_stderr]
            for handle in handles:
                safe_fdclose(handle, cache=self._closed_handle_cache)

        def _wait_and_getattr(self, name):
            """make sure the instance has a certain attr, and return it."""
            while not hasattr(self, name):
                time.sleep(1e-7)
            return getattr(self, name)

        def poll(self):
            """Check if the function has completed.

            Returns
            -------
            None if the function is still executing, and the returncode otherwise
            """
            return self.returncode

        def wait(self, timeout=None):
            """Waits for the process to finish and returns the return code."""
            self.join()
            self._restore_sigint()
            return self.returncode

        #
        # SIGINT handler
        #

        def _signal_int(self, signum, frame):
            """Signal handler for SIGINT - Ctrl+C may have been pressed."""
            # Check if we have already been interrupted. This should prevent
            # the possibility of infinite recursion.
            if self._interrupted:
                return
            self._interrupted = True
            # close file handles here to stop an processes piped to us.
            handles = (
                self.p2cread,
                self.p2cwrite,
                self.c2pread,
                self.c2pwrite,
                self.errread,
                self.errwrite,
            )
            for handle in handles:
                safe_fdclose(handle)
            if self.poll() is not None:
                self._restore_sigint(frame=frame)
            if xt.on_main_thread() and not xp.ON_WINDOWS:
                signal.pthread_kill(threading.get_ident(), signal.SIGINT)

        def _restore_sigint(self, frame=None):
            old = self.old_int_handler
            if old is not None:
                if xt.on_main_thread():
                    signal.signal(signal.SIGINT, old)
                self.old_int_handler = None
            if frame is not None:
                if old is not None and old is not self._signal_int:
                    old(signal.SIGINT, frame)
            if self._interrupted:
                self.returncode = 1

        # The code below (_get_devnull, _get_handles, and _make_inheritable) comes
        # from subprocess.py in the Python 3.4.2 Standard Library
        def _get_devnull(self):
            if not hasattr(self, "_devnull"):
                self._devnull = os.open(os.devnull, os.O_RDWR)
            return self._devnull

        if xp.ON_WINDOWS:

            def _make_inheritable(self, handle):
                """Return a duplicate of handle, which is inheritable"""
                h = xli._winapi.DuplicateHandle(
                    xli._winapi.GetCurrentProcess(),
                    handle,
                    xli._winapi.GetCurrentProcess(),
                    0,
                    1,
                    xli._winapi.DUPLICATE_SAME_ACCESS,
                )
                return Handle(h)

            def _get_handles(self, stdin, stdout, stderr):
                """Construct and return tuple with IO objects:
                p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
                """
                if stdin is None and stdout is None and stderr is None:
                    return (-1, -1, -1, -1, -1, -1)

                p2cread, p2cwrite = -1, -1
                c2pread, c2pwrite = -1, -1
                errread, errwrite = -1, -1

                if stdin is None:
                    p2cread = xli._winapi.GetStdHandle(xli._winapi.STD_INPUT_HANDLE)
                    if p2cread is None:
                        p2cread, _ = xli._winapi.CreatePipe(None, 0)
                        p2cread = Handle(p2cread)
                        xli._winapi.CloseHandle(_)
                elif stdin == subprocess.PIPE:
                    p2cread, p2cwrite = Handle(p2cread), Handle(p2cwrite)
                elif stdin == subprocess.DEVNULL:
                    p2cread = xli.msvcrt.get_osfhandle(self._get_devnull())
                elif isinstance(stdin, int):
                    p2cread = xli.msvcrt.get_osfhandle(stdin)
                else:
                    # Assuming file-like object
                    p2cread = xli.msvcrt.get_osfhandle(stdin.fileno())
                p2cread = self._make_inheritable(p2cread)

                if stdout is None:
                    c2pwrite = xli._winapi.GetStdHandle(xli._winapi.STD_OUTPUT_HANDLE)
                    if c2pwrite is None:
                        _, c2pwrite = xli._winapi.CreatePipe(None, 0)
                        c2pwrite = Handle(c2pwrite)
                        xli._winapi.CloseHandle(_)
                elif stdout == subprocess.PIPE:
                    c2pread, c2pwrite = xli._winapi.CreatePipe(None, 0)
                    c2pread, c2pwrite = Handle(c2pread), Handle(c2pwrite)
                elif stdout == subprocess.DEVNULL:
                    c2pwrite = xli.msvcrt.get_osfhandle(self._get_devnull())
                elif isinstance(stdout, int):
                    c2pwrite = xli.msvcrt.get_osfhandle(stdout)
                else:
                    # Assuming file-like object
                    c2pwrite = xli.msvcrt.get_osfhandle(stdout.fileno())
                c2pwrite = self._make_inheritable(c2pwrite)

                if stderr is None:
                    errwrite = xli._winapi.GetStdHandle(xli._winapi.STD_ERROR_HANDLE)
                    if errwrite is None:
                        _, errwrite = xli._winapi.CreatePipe(None, 0)
                        errwrite = Handle(errwrite)
                        xli._winapi.CloseHandle(_)
                elif stderr == subprocess.PIPE:
                    errread, errwrite = xli._winapi.CreatePipe(None, 0)
                    errread, errwrite = Handle(errread), Handle(errwrite)
                elif stderr == subprocess.STDOUT:
                    errwrite = c2pwrite
                elif stderr == subprocess.DEVNULL:
                    errwrite = xli.msvcrt.get_osfhandle(self._get_devnull())
                elif isinstance(stderr, int):
                    errwrite = xli.msvcrt.get_osfhandle(stderr)
                else:
                    # Assuming file-like object
                    errwrite = xli.msvcrt.get_osfhandle(stderr.fileno())
                errwrite = self._make_inheritable(errwrite)

                return (p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)

        else:
            # POSIX versions
            def _get_handles(self, stdin, stdout, stderr):
                """Construct and return tuple with IO objects:
                p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
                """
                p2cread, p2cwrite = -1, -1
                c2pread, c2pwrite = -1, -1
                errread, errwrite = -1, -1

                if stdin is None:
                    pass
                elif stdin == subprocess.PIPE:
                    p2cread, p2cwrite = os.pipe()
                elif stdin == subprocess.DEVNULL:
                    p2cread = self._get_devnull()
                elif isinstance(stdin, int):
                    p2cread = stdin
                else:
                    # Assuming file-like object
                    p2cread = stdin.fileno()

                if stdout is None:
                    pass
                elif stdout == subprocess.PIPE:
                    c2pread, c2pwrite = os.pipe()
                elif stdout == subprocess.DEVNULL:
                    c2pwrite = self._get_devnull()
                elif isinstance(stdout, int):
                    c2pwrite = stdout
                else:
                    # Assuming file-like object
                    c2pwrite = stdout.fileno()

                if stderr is None:
                    pass
                elif stderr == subprocess.PIPE:
                    errread, errwrite = os.pipe()
                elif stderr == subprocess.STDOUT:
                    errwrite = c2pwrite
                elif stderr == subprocess.DEVNULL:
                    errwrite = self._get_devnull()
                elif isinstance(stderr, int):
                    errwrite = stderr
                else:
                    # Assuming file-like object
                    errwrite = stderr.fileno()

                return (p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)

    #
    # Foreground Thread Process Proxies
    #

    class ProcProxy:
        """This is process proxy class that runs its alias functions on the
        same thread that it was called from, which is typically the main thread.
        This prevents the process from running on a background thread, but enables
        debugger and profiler tools (functions) be run on the same thread that they
        are attempting to debug.
        """

        def __init__(
            self,
            f,
            args,
            stdin=None,
            stdout=None,
            stderr=None,
            universal_newlines=False,
            close_fds=False,
            env=None,
        ):
            self.f = f
            self.args = args
            self.pid = os.getpid()
            self.returncode = None
            self.stdin = stdin
            self.stdout = stdout
            self.stderr = stderr
            self.universal_newlines = universal_newlines
            self.close_fds = close_fds
            self.env = env

        def poll(self):
            """Check if the function has completed via the returncode or None."""
            return self.returncode

        def wait(self, timeout=None):
            """Runs the function and returns the result. Timeout argument only
            present for API compatibility.
            """
            if self.f is None:
                return 0
            env = XSH.env
            enc = env.get("XONSH_ENCODING")
            err = env.get("XONSH_ENCODING_ERRORS")
            spec = self._wait_and_getattr("spec")
            # set file handles
            if self.stdin is None:
                stdin = None
            else:
                if isinstance(self.stdin, int):
                    inbuf = open(self.stdin, "rb", -1)
                else:
                    inbuf = self.stdin
                stdin = io.TextIOWrapper(inbuf, encoding=enc, errors=err)
            stdout = self._pick_buf(self.stdout, sys.stdout, enc, err)
            stderr = self._pick_buf(self.stderr, sys.stderr, enc, err)
            # run the actual function
            try:
                with XSH.env.swap(self.env):
                    r = run_with_partial_args(
                        self.f,
                        {
                            "args": self.args,
                            "stdin": stdin,
                            "stdout": stdout,
                            "stderr": stderr,
                            "spec": spec,
                            "stack": spec.stack,
                        },
                    )
            except SystemExit as e:
                # the alias function is running in the main thread, so we need to
                # catch SystemExit to prevent the entire shell from exiting (see #5689)
                r = e.code if isinstance(e.code, int) else int(bool(e.code))
            except Exception:
                xt.print_exception(source_msg="Exception in " + get_proc_proxy_name(self))
                r = 1
            self.returncode = parse_proxy_return(r, stdout, stderr)
            safe_flush(stdout)
            safe_flush(stderr)
            return self.returncode

        @staticmethod
        def _pick_buf(handle, sysbuf, enc, err):
            if handle is None or handle is sysbuf:
                buf = sysbuf
            elif isinstance(handle, int):
                if handle < 3:
                    buf = sysbuf
                else:
                    buf = io.TextIOWrapper(open(handle, "wb", -1), encoding=enc, errors=err)
            elif hasattr(handle, "encoding"):
                # must be a text stream, no need to wrap.
                buf = handle
            else:
                # must be a binary stream, should wrap it.
                buf = io.TextIOWrapper(handle, encoding=enc, errors=err)
            return buf

        def _wait_and_getattr(self, name):
            """make sure the instance has a certain attr, and return it."""
            while not hasattr(self, name):
                time.sleep(1e-7)
            return getattr(self, name)