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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 create(self, name_or_class, mask, filepath=None, **kwargs):
 """Create a new DCC connection. Return an ``asyncio.Protocol``"""

        if isinstance(name_or_class, type):
            name = name_or_class.type
            protocol = name_or_class
        else:
            name = name_or_class
            protocol = self.protocols[name]
        assert name in DCC_TYPES
        if filepath:
            kwargs.setdefault('limit_rate',
                              self.config['send_limit_rate'])
            kwargs['filepath'] = filepath
            if protocol.type == DCCSend.type:
                kwargs.setdefault('offset', 0)
                kwargs.update(
                    filename_safe=slugify(os.path.basename(filepath)),
                    filesize=os.path.getsize(filepath),
                )
            elif protocol.type == DCCGet.type:
                try:
                    offset = os.path.getsize(filepath)
                except OSError:
                    offset = 0
                kwargs.setdefault('offset', offset)
                kwargs.setdefault('resume', False)
        kwargs.setdefault('port', None)
        f = protocol(
            mask=mask, ip=int(self.bot.ip),
            bot=self.bot, loop=self.loop, **kwargs)

        if kwargs['port']:
            if self.bot.config.get('dcc_sock_factory'):
                sock_factory = maybedotted(self.bot.config.dcc_sock_factory)
                args = dict(sock=sock_factory(self.bot, f.host, f.port))
            else:
                args = dict(host=f.host, port=f.port)
            task = self.bot.create_task(
                self.loop.create_connection(f.factory, **args))
            task.add_done_callback(partial(self.created, f))
        else:
            task = self.bot.create_task(
                self.loop.create_server(
                    f.factory, '0.0.0.0', 0, backlog=1))
            task.add_done_callback(partial(self.created, f))
        return f