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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 parse_requested_expands(query_key, request):
 """ Extracts the value of the expand query string parameter from a request. Supports comma separated lists. :param query_key: The name query string parameter. :param request: Request instance. :return: List of strings representing the values of the expand query string value. """


    requested_expands = []

    for key, val in request.params.items():
        if key == query_key:
            requested_expands += val.split(',')

    return requested_expands