'Get the list of installed files for the distribution
:return: A list of tuples of path, hash and size. Note that hash and
size might be ``None`` for some entries. The path is exactly
as stored in the file (which is as in PEP 376).'

def _get_records(self):

    results = []
    r = self.get_distinfo_resource(u'RECORD')
    with contextlib.closing(r.as_stream()) as stream:
        with CSVReader(stream=stream) as record_reader:
            for row in record_reader:
                missing = [None for i in range(len(row), 3)]
                (path, checksum, size) = (row + missing)
                results.append((path, checksum, size))
    return results
