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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 no_user():
 """ Provides a context with no logged in user. """

    o_token = dcos_acs_token()
    dcos.config.set_val('core.dcos_acs_token', '')
    yield
    dcos.config.set_val('core.dcos_acs_token', o_token)