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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 shell(self, command, *args, environment=None):
 """ Runs a shell command """

        command += ' ' + ' '.join(args)
        command = command.strip()
        self.debug(self.yellow_style('$ %s' % command))
        env = self.env.copy()
        env.update(environment or {})
        return subprocess.call(command, shell=True, env=env)