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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 register_forward_hook(self, hook):
 r"""Registers a forward hook on the block. The hook function is called immediately after :func:`forward`. It should not modify the input or output. Parameters hook : callable The forward hook function of form `hook(block, input, output) -> None`. Returns ------- :class:`mxnet.gluon.utils.HookHandle` """

        handle = HookHandle()
        handle.attach(self._forward_hooks, hook)
        return handle