pydicom.config.assume_implicit_vr_switch = True

If invalid VR encountered, assume file switched to implicit VR

New in version 2.2.

If True (default), when reading an explicit VR file, if a VR is encountered that is not a valid two bytes within A-Z, then assume the original writer switched to implicit VR. This has been seen in particular in some sequences. This does not test that the VR is a valid DICOM VR, just that it has valid characters.