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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 repr(self, changed_widgets=None):
 """Represents the widget as HTML format, packs all the attributes, children and so on. Args: client (App):
 Client instance. changed_widgets (dict):
 A dictionary containing a collection of widgets that have to be updated. The Widget that have to be updated is the key, and the value is its textual repr. """

        if changed_widgets is None:
            changed_widgets={}
        return super(Widget, self).repr(changed_widgets)