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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 _qname(self, name):
 """Convert name to an XML QName e.g. pdf:Producer -> {http://ns.adobe.com/pdf/1.3/}Producer """

        if isinstance(name, QName):
            return name
        if not isinstance(name, str):
            raise TypeError("{} must be str".format(name))
        if name == '':
            return name
        if name.startswith('{'):
            return name
        prefix, tag = name.split(':', maxsplit=1)
        uri = self.NS[prefix]
        return QName(uri, tag)