text: '''
  Represents a single filter on a column.
  '''
  class DrawRequestColumnFilter:
      '''
      Initialize the filter with the column name, filter text,
      and operation (must be "=", "<=", ">=", "<", ">", or "!=").
      '''
      def __init__(self, column_name, filter_text, operation):
          self.name = column_name
          self.text = filter_text
          self.operation = operation
      def __repr__(self):
          return "ColFilter(name=%s, text=%s, op=%s)" % (self.name, self.text, self.operation)
      __str__ = __repr__
  