pydicom is a pure python package for working with DICOM files. It was made for inspecting and modifying DICOM data in an easy "pythonic" way. The modifications can be written again to a new file.
As a pure python package, pydicom can run anywhere python runs without any other requirements, although NumPy is needed if manipulating pixel data.
pydicom is not a DICOM server, and is not primarily about viewing images. It is designed to let you manipulate data elements in DICOM files with python code.
Limitations -- for files with compressed pixel data, pydicom can decompress it (with additional libraries installed) and allow you to manipulate the data, but can only store changed pixel data as uncompressed. Files can always be read and saved (including compressed pixel data that has not been modified), but once decompressed, modified pixel data cannot be compressed again.
pydicom documentation is available on GitHub Pages both for the development (master) version and for the released version. The documentation for the previous 0.9.9 version is still there for reference.
See Getting Started for installation and basic information, and the User Guide for an overview of how to use the pydicom library. To contribute to pydicom, read our contribution guide. To contribute an example or extension of pydicom that does not belong with the core software, see our contribution repository, contrib-pydicom.