cloud-init: Getting the error: No such function check

I have this configuration,

disk_setup:
  /dev/vdb:
    table_type: gpt,
    layout: true

fs_setup:
- label: repo
  filesystem: ext4
  device: /dev/vdb1
  partition: auto

This is the error I get,

2022-06-10 17:30:32,273 - util.py[WARNING]: Failed partitioning operation
No such function check_partition_gpt,_layout to call!
2022-06-10 17:30:32,274 - util.py[DEBUG]: Failed partitioning operation
No such function check_partition_gpt,_layout to call!
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/cloudinit/config/cc_disk_setup.py", line 441, in get_dyn_func
    return globals()[func_name](*func_args)
KeyError: 'check_partition_gpt,_layout'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/cloudinit/config/cc_disk_setup.py", line 148, in handle
    util.log_time(logfunc=LOG.debug,
  File "/usr/lib/python3/dist-packages/cloudinit/util.py", line 2472, in log_time
    ret = func(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/cloudinit/config/cc_disk_setup.py", line 821, in mkpart
    if check_partition_layout(table_type, device, layout):
  File "/usr/lib/python3/dist-packages/cloudinit/config/cc_disk_setup.py", line 547, in check_partition_layout
    found_layout = get_dyn_func(
  File "/usr/lib/python3/dist-packages/cloudinit/config/cc_disk_setup.py", line 446, in get_dyn_func
    raise Exception("No such function %s to call!" % func_name) from e
Exception: No such function check_partition_gpt,_layout to call!

How can I resolve the above error? ---- At the top of my log file, I have * Cloud-init v. 21.4-0ubuntu1~20.04.1 running 'init-local' at Fri, 10 Jun 2022 17:30:22 +0000. Up 8.53 seconds.