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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 process_base_field(cls, field, key):
 """ Preprocess field instances. :param field: Field object :param key: Key where field was found """

        if not field.name:
            field.name = key
        elif key != field.name:
            if not isinstance(field.alias, list):
                field.alias = [key]
            else:
                field.alias.insert(0, key)
            setattr(cls, field.name, field)

        cls.prepare_field(field)

        if field.alias:
            for alias_name in field.alias:
                if key is not alias_name:
                    setattr(cls, alias_name, field)