docs: def transfer_syntax(UID=None, description=None):
      """ Transfer Syntax UID <-> Description lookup.
  
      :param UID: Transfer Syntax UID, returns description
      :param description: Take the description of a transfer syntax and return its UID
      """
      transfer_syntax = {
          "1.2.840.10008.1.2": "Implicit VR Endian: Default Transfer Syntax for DICOM",
          "1.2.840.10008.1.2.1": "Explicit VR Little Endian",
          "1.2.840.10008.1.2.1.99": "Deflated Explicit VR Big Endian",
          "1.2.840.10008.1.2.2": "Explicit VR Big Endian",
          "1.2.840.10008.1.2.4.50": "JPEG Baseline (Process 1): Default Transfer Syntax for Lossy JPEG 8-bit Image Compression",
          "1.2.840.10008.1.2.4.51": "JPEG Baseline (Processes 2 & 4): Default Transfer Syntax for Lossy JPEG 12-bit Image Compression (Process 4 only)",
          "1.2.840.10008.1.2.4.57": "JPEG Lossless, Nonhierarchical (Processes 14)",
          "1.2.840.10008.1.2.4.70": "JPEG Lossless, Nonhierarchical, First-Order Prediction (Processes 14 [Selection Value 1])",
          "1.2.840.10008.1.2.4.80": "JPEG-LS Lossless Image Compression",
          "1.2.840.10008.1.2.4.81": "JPEG-LS Lossy (Near- Lossless) Image Compression",
          "1.2.840.10008.1.2.4.90": "JPEG 2000 Image Compression (Lossless Only)",
          "1.2.840.10008.1.2.4.91": "JPEG 2000 Image Compression",
          "1.2.840.10008.1.2.4.92": "JPEG 2000 Part 2 Multicomponent Image Compression (Lossless Only)",
          "1.2.840.10008.1.2.4.93": "JPEG 2000 Part 2 Multicomponent Image Compression",
          "1.2.840.10008.1.2.4.94": "JPIP Referenced",
          "1.2.840.10008.1.2.4.95": "JPIP Referenced Deflate",
          "1.2.840.10008.1.2.5": "RLE Lossless",
          "1.2.840.10008.1.2.6.1": "RFC 2557 MIME Encapsulation",
          "1.2.840.10008.1.2.4.100": "MPEG2 Main Profile Main Level",
          "1.2.840.10008.1.2.4.102": "MPEG-4 AVC/H.264 High Profile / Level 4.1",
          "1.2.840.10008.1.2.4.103": "MPEG-4 AVC/H.264 BD-compatible High Profile / Level 4.1"
      }
      assert UID or description, "Either Transfer syntax UID or description required"
  
      if UID in transfer_syntax:
          return transfer_syntax[UID]
  
      for key, value in transfer_syntax.iteritems():
          if description == value:
              return key
  
      return None