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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 set(self, name, value):
 u"""Assigns a new XML structure to the node. A literal value, dict or list can be passed in. Works for all nested levels. Dictionary: '<head><a>A</a><b attr="val">B</b></head>' List: '<head><a>A</a><a>B</a><a>C</a></head>' Literals: 'A' """

        try:
            # Searches for a node to assign to.
            element = next(self._xml.iterchildren(tag=name))
        except StopIteration:
            # There is no such node in the XML tree. We create a new one
            # with current root as parent (self._xml).
            element = etree.SubElement(self._xml, name)

        if isinstance(value, dict):
            self.assign_dict(element, value)
        elif isinstance(value, (list, tuple, set)):
            self.assign_sequence_or_set(element, value)
        else:
            # Literal value.
            self.assign_literal(element, value)

        # Clear the aliases.
        self._aliases = None