def scale(reader, writer, column, start, stop, multiple):
  """Multiplies a value over a range of rows.

  Args:
    reader: A FileRecordStream object with input data.
    writer: A FileRecordStream  object to write output data to.
    column: The column of data to modify.
    start: The first row in the range to modify.
    end: The last row in the range to modify.
    multiple: The value to scale/multiply by.
  """
  for i, row in enumerate(reader):
    if i >= start and i <= stop:
      row[column] = type(multiple)(row[column]) * multiple
    writer.appendRecord(row)
Multiplies a value over a range of rows.

  Args:
    reader: A FileRecordStream object with input data.
    writer: A FileRecordStream  object to write output data to.
    column: The column of data to modify.
    start: The first row in the range to modify.
    end: The last row in the range to modify.
    multiple: The value to scale/multiply by.