code: def GetContract(self, script_hash):
          
          if script_hash.ToBytes() in self._contracts.keys():
              return self._contracts[script_hash.ToBytes()]
          return None
docs: Get contract for specified script_hash.
  
          Args:
              script_hash (UInt160): a bytearray (len 20).
  
          Returns:
              Contract: if a contract was found matching the provided script hash, otherwise None