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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 add_child(self, key, value):
 """Adds a child to the Tag To retrieve the child call get_child or access to the Tag.children[key] dictionary. Args: key (str):
 Unique child's identifier, or iterable of keys value (Tag, str):
 can be a Tag, an iterable of Tag or a str. In case of iterable of Tag is a dict, each item's key is set as 'key' param """

        if type(value) in (list, tuple, dict):
            if type(value)==dict:
                for k in value.keys():
                    self.add_child(k, value[k])
                return
            i = 0
            for child in value:
                self.add_child(key[i], child)
                i = i + 1
            return

        if hasattr(value, 'attributes'):
            value.attributes['data-parent-widget'] = self.identifier
            value._parent = self

        if key in self.children:
            self._render_children_list.remove(key)
        self._render_children_list.append(key)

        self.children[key] = value