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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def command_executor(self):
 """Get the appropriate command executor URL for the Selenium server running in the Docker container."""

        ip_address = self.ip_address if self.ip_address else '127.0.0.1'
        return 'http://{}:{}/wd/hub'.format(ip_address, self.port)