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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 _get_header(self):
 """Get the header from the deinfed header rows, for use on references or resources where the schema has not been run"""


        try:
            header_lines = [int(e) for e in str(self.get_value('headerlines', 0)).split(',')]
        except ValueError as e:
            header_lines = [0]

        # We're processing the raw datafile, with no schema.
        header_rows = islice(self.row_generator, min(header_lines), max(header_lines) + 1)

        from tableintuit import RowIntuiter
        headers = RowIntuiter.coalesce_headers(header_rows)

        return headers