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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 _create_selector(int_type, func, trait, **kwargs):
 """Create a selector of the specified type. Also attaches the function `func` as an `on_trait_change` listener for the trait `trait` of the selector. This is an internal function which should not be called by the user. Parameters int_type: type The type of selector to be added. func: function The call back function. It should take atleast two arguments. The name of the trait and the value of the trait are passed as arguments. trait: string The name of the Selector trait whose change triggers the call back function `func`. """

    interaction = _add_interaction(int_type, **kwargs)
    if func is not None:
        interaction.on_trait_change(func, trait)
    return interaction