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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 connect_button(instance, prop, widget):
 """ Connect a button with a callback method Parameters instance : object The class instance that the callback method is attached to prop : str The name of the callback method widget : QtWidget The Qt widget to connect. This should implement the ``clicked`` method """

    widget.clicked.connect(getattr(instance, prop))