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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_result_format(result_format):
 """This is a simple helper utility that can be used to parse a string result_format into the dict format used internally by great_expectations. It is not necessary but allows shorthand for result_format in cases where there is no need to specify a custom partial_unexpected_count."""

    if isinstance(result_format, string_types):
        result_format = {
            'result_format': result_format,
            'partial_unexpected_count': 20
        }
    else:
        if 'partial_unexpected_count' not in result_format:
            result_format['partial_unexpected_count'] = 20

    return result_format