##
21.6 Shortcut functions for the default canvas

For the default canvas ( see Section 21.3), you can call the following functions provided in the `canvas` module directly:

`line`( | linestyle, x1, y1, x2, y2)

  Calls the method with the same name on the default canvas object.

`polygon`( | linestyle, fillstyle, [(x1,y1), ..., (xn, yn)])

  Calls the method with the same name on the default canvas object.

`rectangle`( | linestyle, fillstyle, x1, y1, x2, y2, shadow=None)

  Calls the method with the same name on the default canvas object. Parameter shadow is either None or tuple (xdelta, ydelta, shadowstyle). If non-None, a shadow of shadowstyle ( see Section 16) is drawn beneath the polygon at the offset (xdelta, ydelta).

`ellipsis`( | linestyle, fillstyle, x, y, radius, y_elongation=1, start=0, end=360, shadow=None)

  Calls the method with the same name on the default canvas object. Parameter shadow is either None or tuple (xdelta, ydelta, shadowstyle). If non-None, a shadow of shadowstyle ( see Section 16) is drawn beneath the polygon at the offset (xdelta, ydelta).

`round_rectangle`( | linestyle, fillstyle, x1, y2, x2, y2,radius, shadow=None)

  Calls the method with the same name on the default canvas object. Parameter shadow is either None or tuple (xdelta, ydelta, shadowstyle). If non-None, a shadow of shadowstyle ( see Section 16) is drawn beneath the polygon at the offset (xdelta, ydelta).

`curve`( | linestyle, [(x1,y2), ..., (xn, yn)])

  Calls the method with the same name on the default canvas object.

`show`( | x, y, text)

  Calls the method with the same name on the default canvas object.

`verbatim`( | str)

  Calls the method with the same name on the default canvas object.

`default_canvas`( | )

  Return the default canvas.

`clip`( | x1, y1, x2, y2)

  Calls the method with the same name on the default canvas object.

`clip_ellipsis`( | x, y, radius, y_elongation)

  Calls the method with the same name on the default canvas object.

`clip_polygon`( | [(x1,y2),(x2,y2), ..., (xn, yn)])

  Calls the method with the same name on the default canvas object.

`endclip`( | )

  Calls the method with the same name on the default canvas object.