'Execute python script in other process.
Raises:
SurviveException: contains the error message of the script if it terminated before timeout'

def execute(self):

    self.start()
    self.join(self.timeout)
    if self.is_alive():
        self.p.terminate()
        self.p.kill()
        self.join()
    elif (len(self.err) > 0):
        output = (u'STDOUT:    \n\n\n' + self.out.decode('utf-8'))
        output += (u'\n\n\n    STDERR:    \n\n\n' + self.err.decode('utf-8'))
        raise AssertionError(output)
