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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 env(*args, **kwargs):
 """ Returns the first environment variable set if none are non-empty, defaults to "" or keyword arg default """

    for arg in args:
        value = os.environ.get(arg, None)
        if value:
            return value
    return kwargs.get("default", "")