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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 return_xml(element_tree):
 """Return an XML Element. Args: element_tree (Element):
 XML Element to be returned. If sent as a ``str``, this function will attempt to convert it to an ``Element``. Returns: Element: An XML Element. Raises: TypeError: if `element_tree` is not of type ``Element`` and it cannot be converted from a ``str``. Examples: Traceback (most recent call last):
 TypeError """

    if isinstance(element_tree, ET.Element):
        return element_tree
    try:
        return ET.fromstring(element_tree)
    except TypeError:
        raise TypeError('{} takes either {} or {} type.'
                        .format(repr(return_xml.__name__),
                                repr(str.__name__),
                                repr(ET.Element.__name__)))