code: def read(cls, five9, external_id):
          
          results = cls.search(five9, {cls.__uid_field__: external_id})
          if not results:
              return None
          return results[0]
docs: Return a record singleton for the ID.
  
          Args:
              five9 (five9.Five9): The authenticated Five9 remote.
              external_id (mixed): The identified on Five9. This should be the
                  value that is in the ``__uid_field__`` field on the record.
  
          Returns:
              BaseModel: The record, if found. Otherwise ``None``