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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_fields(self, result, field_name):
 """ If Schema access, parse fields and build respective lists """

        field_list = []
        for key, value in result.get('schema', {}).get(field_name, {}).items():
            if key not in field_list:
                field_list.append(key)
        return field_list