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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 createJsbConfig(self):
 """ Create JSB config file using ``sencha create jsb``. :return: The created jsb3 config as a string. """

        tempdir = mkdtemp()
        tempfile = join(tempdir, 'app.jsb3')
        cmd = ['sencha', 'create', 'jsb', '-a', self.url, '-p', tempfile]
        log.debug('Running: %s', ' '.join(cmd))
        call(cmd)
        jsb3 = open(tempfile).read()
        rmtree(tempdir)
        return jsb3