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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 _insert(self, dom_group, idx=None, prepend=False, name=None):
 """Inserts a DOMGroup inside this element. If provided at the given index, if prepend at the start of the childs list, by default at the end. If the child is a DOMElement, correctly links the child. If the DOMGroup have a name, an attribute containing the child is created in this instance. """

        if idx and idx < 0:
            idx = 0
        if prepend:
            idx = 0
        else:
            idx = idx if idx is not None else len(self.childs)
        if dom_group is not None:
            if not isinstance(dom_group, Iterable) or isinstance(
                dom_group, (DOMElement, str)
            ):
                dom_group = [dom_group]
            for i_group, elem in enumerate(dom_group):
                if elem is not None:
                    # Element insertion in this DOMElement childs
                    self.childs.insert(idx + i_group, elem)
                    # Managing child attributes if needed
                    if issubclass(elem.__class__, DOMElement):
                        elem.parent = self
                    if name:
                        setattr(self, name, elem)