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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 _vpn_signal_handler(self, args):
 """Called on NetworkManager PropertiesChanged signal"""

        # Args is a dictionary of changed properties
        # We only care about changes in ActiveConnections
        active = "ActiveConnections"
        # Compare current ActiveConnections to last seen ActiveConnections
        if active in args.keys() and sorted(self.active) != sorted(args[active]):
            self.active = args[active]
            self.py3.update()