code: def _read_requires_python(metadata):
      
      # TODO: Support more metadata formats.
      value = metadata.dictionary.get("requires_python")
      if value is not None:
          return value
      if metadata._legacy:
          value = metadata._legacy.get("Requires-Python")
          if value is not None and value != "UNKNOWN":
              return value
      return ""
docs: Read wheel metadata to know the value of Requires-Python.
  
      This is surprisingly poorly supported in Distlib. This function tries
      several ways to get this information:
  
      * Metadata 2.0: metadata.dictionary.get("requires_python") is not None
      * Metadata 2.1: metadata._legacy.get("Requires-Python") is not None
      * Metadata 1.2: metadata._legacy.get("Requires-Python") != "UNKNOWN"