def add_struct(self):
    """Appends and returns a struct value as the next value in the list."""
    struct_value = self.values.add().struct_value
    # Clear will mark struct_value modified which will indeed create a struct.
    struct_value.Clear()
    return struct_value
Appends and returns a struct value as the next value in the list.
deps/protobuf/python/google/protobuf/internal/well_known_types.py