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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 register_module(module=None):
 """ Registers given module or caller introspected module in the candidates modules for tracing. :param module: Module to register. :type module: ModuleType :return: Definition success. :rtype: bool """


    global REGISTERED_MODULES

    if module is None:
        # Note: inspect.getmodule() can return the wrong module if it has been imported with different relatives paths.
        module = sys.modules.get(inspect.currentframe().f_back.f_globals["__name__"])

    REGISTERED_MODULES.add(module)
    return True