Error during installation of "builder" app - ImportError

I am encountering an issue while trying to install the “builder” app on my Frappe site using the command:
Frappe Framework : v14

bench --site cms.com install-app builder

Installing builder...
Updating DocTypes for builder       : [================    ] 83%An error occurred while installing builder: Module import failed for Builder Page, the DocType you're trying to open might be deleted.<br> Error: cannot import name 'is_safe_exec_enabled' from 'frappe.utils.safe_exec' (/home/nayar/frappe-cms/apps/frappe/frappe/utils/safe_exec.py)
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 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "apps/builder/builder/builder/doctype/builder_page/builder_page.py", line 14, in <module>
    from frappe.utils.safe_exec import safe_exec, is_safe_exec_enabled
ImportError: cannot import name 'is_safe_exec_enabled' from 'frappe.utils.safe_exec' (apps/frappe/frappe/utils/safe_exec.py)

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

Traceback (most recent call last):
  File "apps/frappe/frappe/commands/site.py", line 415, in install_app
    _install_app(app, verbose=context.verbose, force=force)
  File "apps/frappe/frappe/installer.py", line 297, in install_app
    sync_for(name, force=force, reset_permissions=True)
  File "apps/frappe/frappe/model/sync.py", line 109, in sync_for
    import_file_by_path(
  File "apps/frappe/frappe/modules/import_file.py", line 145, in import_file_by_path
    import_doc(
  File "apps/frappe/frappe/modules/import_file.py", line 242, in import_doc
    doc.insert()
  File "apps/frappe/frappe/model/document.py", line 289, in insert
    self.run_post_save_methods()
  File "apps/frappe/frappe/model/document.py", line 1088, in run_post_save_methods
    self.run_method("on_update")
  File "apps/frappe/frappe/model/document.py", line 915, in run_method
    out = Document.hook(fn)(self, args, *kwargs)
  File "apps/frappe/frappe/model/document.py", line 1277, in composer
    return composed(self, method, args, *kwargs)
  File "apps/frappe/frappe/model/document.py", line 1259, in runner
    add_to_return_value(self, fn(self, args, *kwargs))
  File "apps/frappe/frappe/model/document.py", line 912, in fn
    return method_object(*args, **kwargs)
  File "apps/frappe/frappe/core/doctype/doctype/doctype.py", line 407, in on_update
    self.run_module_method("on_doctype_update")
  File "apps/frappe/frappe/core/doctype/doctype/doctype.py", line 505, in run_module_method
    module = load_doctype_module(self.name, self.module)
  File "apps/frappe/frappe/modules/utils.py", line 249, in load_doctype_module
    raise ImportError(msg) from e
ImportError: Module import failed for Builder Page, the DocType you're trying to open might be deleted.<br> Error: cannot import name 'is_safe_exec_enabled' from 'frappe.utils.safe_exec' (apps/frappe/frappe/utils/safe_exec.py)

Hi @Masky,

In version 14 of ERPNext, the ‘builder’ feature is not supported due to some issues related to dependencies. However, it works fine in version 15 and any version above 15.

CC: @surajshetty

Thank You!

It still gives this error on Frappe 15 (frappe 15.3.0) and ERPNext 15 (erpnext 15.4.0)