# Frequently asked questions

## General

### What happened to import dicom?

Starting in version 1.0, pydicom changed the library import from `import dicom` to `import pydicom`. If you’re used to using the earlier versions of pydicom see the transitioning guide on how to make the change.

### How do I cite pydicom?

The easiest method is probably to find the Zenodo DOI for the version you are using and then entering your required citation style in the Cite as box.

Alternatively, you can use something along the lines of:

    Mason, D. L., et al, pydicom: An open source DICOM library, https://github.com/pydicom/pydicom [Online; accessed YYYY-MM-DD].

## Installation

### What are pydicom’s prerequisites?

#### Required

pydicom requires Python.

#### Optional

When manipulating Pixel Data it’s recommended you install NumPy. When dealing with JPEG compressed Pixel Data see this table for which libraries are required.

### What version of Python can I use?

pydicom version | Release date | Python versions
--- | --- | ---
1.0 | March 2018 | 2.7, 3.4, 3.5, 3.6
1.1 | June 2018 | 2.7, 3.4, 3.5, 3.6
1.2 | October 2018 | 2.7, 3.4, 3.5, 3.6
1.3 | July 2019 | 2.7, 3.4, 3.5, 3.6
1.4 | January 2020 | 2.7, 3.5, 3.6, 3.7, 3.8
2.0 | May 2020 | 3.5, 3.6, 3.7, 3.8
2.1 | ~November 2020 | 3.6, 3.7, 3.8, 3.9
2.2 | ~May 2021 | 3.6, 3.7, 3.8, 3.9
2.3 | ~November 2021 | 3.6, 3.7, 3.8, 3.9, 3.10

### What about support for Python 2.7?

Python 2.7 reached end of life on 1st January, 2020 and is no longer supported by pydicom. More information is available here.