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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 load_class(module_name, class_name):
 """Return class object specified by module name and class name. Return None if module failed to be imported. :param module_name: string module name :param class_name: string class name """

    try:
        plugmod = import_module(module_name)
    except Exception as exc:
        warn("Importing built-in plugin %s.%s raised an exception: %r" %
             (module_name, class_name, repr(exc)), ImportWarning)
        return None
    else:
        return getattr(plugmod, class_name)