code: def pyobjc_method_signature(signature_str):
          
          _objc_so.PyObjCMethodSignature_WithMetaData.restype = ctypes.py_object
          return _objc_so.PyObjCMethodSignature_WithMetaData(ctypes.create_string_buffer(signature_str), None, False)
docs: Return a PyObjCMethodSignature object for given signature string.
  
          :param signature_str: A byte string containing the type encoding for the method signature
          :return: A method signature object, assignable to attributes like __block_signature__
          :rtype: <type objc._method_signature>