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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 clean_env(uchroot_cmd, varnames):
 """Returns a uchroot cmd that runs inside a filtered environment."""

    env = uchroot_cmd["/usr/bin/env"]
    __clean_env = env["-u", ",".join(varnames)]
    return __clean_env