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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 warn_if_fields_defined_in_meta(fields, Meta):
 """Warns user that fields defined in Meta.fields or Meta.additional will be ignored :param dict fields: A dictionary of fields name field object pairs :param Meta: the schema's Meta class """

    if getattr(Meta, "fields", None) or getattr(Meta, "additional", None):
        declared_fields = set(fields.keys())
        if (
            set(getattr(Meta, "fields", set())) > declared_fields
            or set(getattr(Meta, "additional", set())) > declared_fields
        ):
            warnings.warn(
                "Only explicitly-declared fields will be included in the Schema Object. "
                "Fields defined in Meta.fields or Meta.additional are ignored."
            )