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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 read_existing_paths(bt_table):
 """Return the SGF filename for each existing eval record."""

    rows = bt_table.read_rows(
        filter_=row_filters.ColumnRangeFilter(
            METADATA, SGF_FILENAME, SGF_FILENAME))
    names = (row.cell_value(METADATA, SGF_FILENAME).decode() for row in rows)
    processed = [os.path.splitext(os.path.basename(r))[0] for r in names]
    return processed