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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_include_fields(request):
 """Retrieve include_fields values from the request """

    include_fields = []
    rif = request.get("include_fields", "")
    if "include_fields" in request:
        include_fields = [x.strip()
                          for x in rif.split(",")
                          if x.strip()]
    if "include_fields[]" in request:
        include_fields = request['include_fields[]']
    return include_fields