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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 url_path(self):
        ''' The last path component for the basename of the configured filename.

        '''
        if self.failed:
            return None
        else:
            # TODO should fix invalid URL characters
            return '/' + os.path.splitext(os.path.basename(self._runner.path))[0]