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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 find_node(self, name, create=False):
 """Find a node in the zone, possibly creating it. @param name: the name of the node to find @type name: dns.name.Name object or string @param create: should the node be created if it doesn't exist? @type create: bool @raises KeyError: the name is not known and create was not specified. @rtype: dns.node.Node object """


        name = self._validate_name(name)
        node = self.nodes.get(name)
        if node is None:
            if not create:
                raise KeyError
            node = self.node_factory()
            self.nodes[name] = node
        return node