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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 get_request_meta(request, key):
 """ Given a key, it returns a cleaned up version of the value from request.META, or None """

    value = request.META.get(key, request.META.get(key.replace('_', '-'), '')).strip()
    if value == '':
        return None
    return value