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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 deregister(cls, name: str) -> None: """Deregisters a registered connection plugin by its name Args: name: name of the connection plugin to deregister Raises: :obj:`nornir.core.exceptions.ConnectionPluginNotRegistered` """

        if name not in cls.available:
            raise ConnectionPluginNotRegistered(
                f"Connection {name!r} is not registered"
            )
        cls.available.pop(name)