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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 check_settings(required_settings):
 """ Checks all settings required by a module have been set. If a setting is required and it could not be found a NotImplementedError will be raised informing which settings are missing. :param required_settings: List of settings names (as strings) that are anticipated to be in the settings module. :return: None. """

    defined_settings = [
        setting if hasattr(settings, setting) else None for setting in required_settings
    ]

    if not all(defined_settings):
        raise NotImplementedError(
            'The following settings have not been set: %s' % ', '.join(
                set(required_settings) - set(defined_settings)
            )
        )