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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 _validate_field_headers(reader):
 """ Perform some validations on the CSV headers A `type` field header must be present & all field headers must be strings. :param reader: csv reader object """


        link = 'tools.ietf.org/html/rfc4180#section-2'

        for field in reader.fieldnames:
            if not isinstance(field, str):
                fail('All headers in your CSV payload must be '
                     'strings.', link)

        if 'type' not in reader.fieldnames:
            fail('A type header must be present in your CSV '
                 'payload.', link)