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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 aimport(self, parameter_s='', stream=None):
 """%aimport => Import modules for automatic reloading. %aimport List modules to automatically import and not to import. %aimport foo Import module 'foo' and mark it to be autoreloaded for %autoreload 1 %aimport foo, bar Import modules 'foo', 'bar' and mark them to be autoreloaded for %autoreload 1 %aimport -foo Mark module 'foo' to not be autoreloaded for %autoreload 1 """

        modname = parameter_s
        if not modname:
            to_reload = sorted(self._reloader.modules.keys())
            to_skip = sorted(self._reloader.skip_modules.keys())
            if stream is None:
                stream = sys.stdout
            if self._reloader.check_all:
                stream.write("Modules to reload:\nall-except-skipped\n")
            else:
                stream.write("Modules to reload:\n%s\n" % ' '.join(to_reload))
            stream.write("\nModules to skip:\n%s\n" % ' '.join(to_skip))
        elif modname.startswith('-'):
            modname = modname[1:]
            self._reloader.mark_module_skipped(modname)
        else:
            for _module in ([_.strip() for _ in modname.split(',')]):
                top_module, top_name = self._reloader.aimport_module(_module)

                # Inject module to user namespace
                self.shell.push({top_name: top_module})