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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_key_field(ui, ui_option_name, default_val=0, default_is_number=True):
 """ parse an option from a UI object as the name of a key field. If the named option is not set, return the default values for the tuple. :return: a tuple of two items, first is the value of the option, second is a boolean value that indicates whether the value is a column name or a column number (numbers start at 0). """

  key = default_val
  key_is_field_number = default_is_number
  if ui.optionIsSet(ui_option_name):
    key = ui.getValue(ui_option_name)
    try:
      key = int(key) - 1
      key_is_field_number = True
    except ValueError:
      key_is_field_number = False
  return key, key_is_field_number