Traceback (most recent call last):
  File "apps/frappe/frappe/modules/utils.py", line 245, in load_doctype_module
    doctype_python_modules[key] = frappe.get_module(module_name)
  File "apps/frappe/frappe/__init__.py", line 1340, in get_module
    return importlib.import_module(modulename)
  File "/usr/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 992, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1004, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'frappe.core.doctype.none'

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

Traceback (most recent call last):
  File "apps/frappe/frappe/app.py", line 94, in application
    response = frappe.api.handle()
  File "apps/frappe/frappe/api.py", line 54, in handle
    return frappe.handler.handle()
  File "apps/frappe/frappe/handler.py", line 47, in handle
    data = execute_cmd(cmd)
  File "apps/frappe/frappe/handler.py", line 85, in execute_cmd
    return frappe.call(method, **frappe.form_dict)
  File "apps/frappe/frappe/__init__.py", line 1620, in call
    return fn(*args, **newargs)
  File "apps/frappe/frappe/utils/print_format.py", line 129, in download_pdf
    doc = doc or frappe.get_doc(doctype, name)
  File "apps/frappe/frappe/__init__.py", line 1197, in get_doc
    doc = frappe.model.document.get_doc(*args, **kwargs)
  File "apps/frappe/frappe/model/document.py", line 72, in get_doc
    controller = get_controller(doctype)
  File "apps/frappe/frappe/model/base_document.py", line 82, in get_controller
    site_controllers[doctype] = _get_controller()
  File "apps/frappe/frappe/model/base_document.py", line 64, in _get_controller
    module = load_doctype_module(doctype, module_name)
  File "apps/frappe/frappe/modules/utils.py", line 249, in load_doctype_module
    raise ImportError(msg) from e
ImportError: Module import failed for None, the DocType you're trying to open might be deleted.
 Error: No module named 'frappe.core.doctype.none'