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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 describe_connection(self):
 """Return string representation of the device, including the connection state"""

        if self.device==None:
            return "%s [disconnected]" % (self.name)
        else:
            return "%s connected to %s %s version: %s [serial: %s]" % (self.name, 
                self.vendor_name, self.product_name,
                self.version_number, self.serial_number)