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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 messaging(_context, repository, reset_on_start=False):
 """ Directive for setting up the user message resource in the appropriate repository. :param str repository: The repository to create the user messages resource in. """

    discriminator = ('messaging', repository)
    reg = get_current_registry()
    config = Configurator(reg, package=_context.package)
    _context.action(discriminator=discriminator, # pylint: disable=E1101
                    callable=config.setup_system_repository,
                    args=(repository,),
                    kw=dict(reset_on_start=reset_on_start))