Refactored Bot Code

refactored.py

class Member(dict):
    def __init__(self, name, *args, **kwargs):
        super(Member, self).__init__(**kwargs)
        self.name = name

class MemberStore(object):

    def __init__(self):
        self.members = {}
        self.aliases = {}

    def register_alias(self, user, alias):
        self.aliases[alias] = user

    def get_user(self, name):
        if name in self.members:
            return self.members[name]
        if name in self.aliases:
            return self.get_user(self.aliases[name])
        self.members[name] = Member(name)
        return self.members[name]


_members = MemberStore()
_commands = {}

def _command(name):
    def _decorator(func):
        _commands[name] = func
        return func
    return _decorator

@_command("faggot")
def faggot(user):
    global _members
    user = _members.get_user(user)
    counter = user.get('faggot', 0) + 1
    user['faggot'] = counter
    return f"Der Benutzer {user} hat nun {counter} fgts."

@_command("faggot")
def alias(line):
    global _members
    user, alias = line.split(" ")
    _members.register_alias(user, alias)
    return f"Der Benutzer {user} hat nun den Alias {alias}"    

def parse_command(line):
    cmd, *data = line.split(" ", 1)
    if len(data):
        data = data[0]
    else:
        data = ""

    return cmd, data

async def execute_command(client, message, str):
    cmd, data = parse_command(str)
    result = _commands[cmd](data)
    return await client.send_message(message.channel, result)