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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 stage():
 """Option to do something on the staging server."""

    common_conf()
    env.user = settings.LOGIN_USER_STAGE
    env.machine = 'stage'
    env.host_string = settings.HOST_STAGE
    env.hosts = [env.host_string, ]