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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 _remove_root_tag_prefix(v):
 """ Removes 'voe' namespace prefix from root tag. When we load in a VOEvent, the root element has a tag prefixed by the VOE namespace, e.g. {http://www.ivoa.net/xml/VOEvent/v2.0}VOEvent Because objectify expects child elements to have the same namespace as their parent, this breaks the python-attribute style access mechanism. We can get around it without altering root, via e.g who = v['{}Who'] Alternatively, we can temporarily ditch the namespace altogether. This makes access to elements easier, but requires care to reinsert the namespace upon output. I've gone for the latter option. """

    if v.prefix:
        # Create subelement without a prefix via etree.SubElement
        etree.SubElement(v, 'original_prefix')
        # Now carefully access said named subelement (without prefix cascade)
        # and alter the first value in the list of children with this name...
        # LXML syntax is a minefield!
        v['{}original_prefix'][0] = v.prefix
        v.tag = v.tag.replace(''.join(('{', v.nsmap[v.prefix], '}')), '')
        # Now v.tag = '{}VOEvent', v.prefix = None
    return