Can't call script method.

'''The error.'''
'''
Traceback (most recent call last):
  File "d:\muddev\evennia\evennia\commands\cmdhandler.py", line 591, in _run_command
    ret = cmd.func()
  File ".\commands\combat.py", line 28, in func
    self.caller.db.combat_handler.attack(target)
AttributeError: 'NoneType' object has no attribute 'attack'

An untrapped error occurred.
(Traceback was logged 19-08-04 10:34:32-04).
'''

'''The player's script creation.'''
class Player_Character(DefaultCharacter):
    def at_object_creation(self):
        self.scripts.add(CombatHandler)

'''The attacking command within commands\combat.py'''
class CmdStaveBash(BaseCommand):
    '''
    Use your staff to bash an enemy.

    Usage:
        bash <target>
    '''
    key = 'bash'
    help_category = 'combat'

    def func(self):
        if not self.args:
            self.caller.msg('Usage: bash <target>')
            return
        target = self.caller.search(self.args)
        if not target:
            self.caller.msg('That target does not exist!')
            return
        if not target.attributes.has('hp'):
            self.caller.msg('You cannot attack that target!')
            return
        self.caller.db.combat_handler.attack(target) # LINE 28

'''The combat handler script'''
class CombatHandler(DefaultScript):
    key = 'combat_handler'

    def attack(self, target):
        damage = 20

        now = time.time()
        lastcast = self.db.stave_bash
        cooldown = lastcast + 3
        time_remaining = cooldown - now

        if time_remaining > 0:
            if time_remaining >= 2:
                message = f"You need to wait {int(time_remaining)} more seconds."
            elif time_remaining >= 1 and time_remaining < 2:
                message = f"You need to wait {int(time_remaining)} more second."
            elif time_remaining < 1:
                message = f"You are in the middle of something."
            self.obj.msg(message)
            return

        # roll = random.randint(1, 100)
        # success = random.randint(5, 95)
        roll = 100
        success = 0

        if roll > success:
            self.obj.msg(f'[Success: {success} Roll: {roll}] You bash {target} with your stave!')
            self.take_damage(target, damage)
        else:
            self.obj.msg(f'[Success: {success} Roll: {roll}] You miss {target} with your stave!')
        utils.delay(3, self.unbusy)
        self.db.stave_bash = now

    def take_damage(self, target, damage):
        mob = target.key
        location = target.location

        target.db.hp -= damage
        hp = target.db.hp
        location.msg_contents(f'{mob} has {hp} health remaining!')
        if hp >= 1:
            target.db.ko = False
        elif hp <= 0 and self.db.ko != True:
            target.db.ko = True
            location.msg_contents(f'{mob} falls unconscious!')
        if hp <= -100:
            okay = target.delete()
            if not okay:
                location.msg_contents(f'\nERROR: {mob} not deleted, probably because delete() returned False.')
            else:
                location.msg_contents(f'{mob} breathes a final breath and expires.')
        return

    def unbusy(self):
            self.obj.msg('|yYou are no longer busy.|n')

'''Puppeted character's examine'''
'''
------------------------------------------------------------------------------
Name/key: Bobby (#25)
Aliases: a bobby(#25),one bobby(#25)s
Session id(s): #4
Account: Kovitikus
Account Perms: <Superuser>
Typeclass: Player_Character (typeclasses.characters.Player_Character)
Location: Hoff's Bar (#7)
Home: Limbo (#2)
Permissions: <None> [Superuser]
Locks:      call:false(); control:perm(Developer); delete:perm(Admin);
      edit:perm(Admin); examine:perm(Builder); get:false();
      puppet:pperm(Developer); tell:perm(Admin); view:all()
Stored Cmdset(s):
 commands.default_cmdsets.CharacterCmdSet [DefaultCharacter] (Union, prio 0)
Merged Cmdset(s):
 evennia.commands.cmdset.CmdSet [ChannelCmdSet] (Union, prio 101)
 commands.default_cmdsets.CharacterCmdSet [DefaultCharacter] (Union, prio 0)
 commands.default_cmdsets.AccountCmdSet [DefaultAccount] (Union, prio -10)
 commands.default_cmdsets.SessionCmdSet [DefaultSession] (Union, prio -20)
Commands available to Bobby (result of Merged CmdSets):
   about, access, accounts, addcom, alias, allcom, ban, bash, batchcode,
  batchcommands, boot, cboot, ccreate, cdesc, cdestroy, cemit, channels,
  charcreate, chardelete, chargen, clock, cmdsets, color, copy, cpattr,
  create, cwho, delcom, desc, destroy, dig, drop, emit, examine, find, force,
  get, give, grapevine2chan, help, home, ic, inventory, irc2chan, ircstatus,
  link, lock, look, mudinfo, mvattr, name, nick, objects, open, option, page,
  password, perm, pose, public, py, quell, quit, reload, reset, rss2chan, say,
  script, scripts, server, service, sessions, set, setdesc, sethelp, sethome,
  shutdown, south, spawn, style, tag, tel, tickers, time, tunnel, typeclass,
  unban, unlink, userpassword, wall, whisper, who, wipe
Scripts:
 'combat_handler' (inf/inf, inf repeats):
Persistent attributes:
 figure = {'gender': 'male', 'height': 'very tall', 'build': 'ample'}
 facial = {'face': 'freckled', 'eye_color': 'light grey', 'nose': 'hooked', 'lips':[...]
 hair = {'hair_color': None, 'texture': None, 'length': 'bald', 'style': None}
 prelogout_location = Hoff's Bar
------------------------------------------------------------------------------
'''