human
Complete this python program:
def check_package_data_first(command):
assistant
#Here is the Python code you requested.

    """decorator for checking package_data before running a given command
    Probably only needs to wrap build_py
    """
    class DecoratedCommand(command, ):
        def run(self):
            check_package_data(self.package_data)
            command.run(self)
    return DecoratedCommand