Log message:
py-pydicom: Update to 1.2.1.

From Eric A. Borisch in pull request NetBSD/pkgsrc#40.

-   Do not derive Dataset from dict (#767)
    -   fixes side effects from initializing with another dataset
-   Added missing dict methods that are passed to the tags dict
-   Adapted documentation to Dataset changes
-   Make sure that the retry order config is reset in the test (#772)

Log message:
py-pydicom: Import py-pydicom-1.2.0 as biology/py-pydicom

Pydicom is a pure Python package for working with DICOM files such as medical
images, reports, and radiotherapy objects.

Pydicom makes it easy to read these complex files into natural pythonic
structures for easy manipulation. Modified datasets can be written again to
DICOM format files.

Packaged by Eric A. Borisch via NetBSD/pkgsrc#37, thank you Eric!