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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 run_command(command, env):
 """Run command in sub process. Runs the command in a sub process with the variables from `env` added in the current environment variables. Parameters command: List[str] The command and it's parameters env: Dict The additional environment variables Returns ------- int The return code of the command """

    # copy the current environment variables and add the vales from
    # `env`
    cmd_env = os.environ.copy()
    cmd_env.update(env)

    p = Popen(command,
              universal_newlines=True,
              bufsize=0,
              shell=False,
              env=cmd_env)
    _, _ = p.communicate()

    return p.returncode