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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 configure(config=None, bind_in_runtime=True):
 """Create an injector with a callable config or raise an exception when already configured."""

    global _INJECTOR

    with _INJECTOR_LOCK:
        if _INJECTOR:
            raise InjectorException('Injector is already configured')

        _INJECTOR = Injector(config, bind_in_runtime=bind_in_runtime)
        logger.debug('Created and configured an injector, config=%s', config)
        return _INJECTOR