# class `RadioGroup`

A RadioGroup is used to coordinate the activity of a group of RadioButtons. It ensures that only one of the RadioButtons is on at a time, and provides a `value` property which is equal to the `value` of the currently selected RadioButton. It also provides an `action` property which is invoked when the user changes the selection.

You can iterate over the RadioButtons contained in a RadioGroup, which means you can use a RadioGroup directly in the place_row and place_column methods of a container.

## Properties

`value`
  The value of the currently selected RadioButton. Setting this property updates the states of the RadioButtons accordingly.

> `action`
>   Action to perform when the value changes as a result of the user clicking on a radio button.

## Constructor

`RadioGroup(items)`
  Constructs a RadioGroup containing the given list of RadioButtons.

## Methods

`add_item(`item`)
add_items([`item, ...])
  Adds one or more RadioButtons to this group.

`remove_item(`item`)
remove_items([`item, ...])
  Removes one or more RadioButtons from this group.

## Operations

iter(group)
  Returns an iterator over the RadioButtons contained in the group.

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