Error when starting the server (No module named 'jinja2_humanize_extension')

[staedi]

Hello,
Today I installed prefect and tried to test a bit with prefect start server but it failed with the error message with jinja2_humanize_extension library.

ModuleNotFoundError: No module named 'jinja2_humanize_extension'

I created a mamba (conda) environment with Python 3.11. No other libraries other than prefect were installed (only Python 3.11 and prefect).

Much appreciated if I got a guidance with this behavior.
Thanks in advance!

prefect version

Version:             2.18.0
API version:         0.8.4
Python version:      3.11.9
Git commit:          1006d2d8
Built:               Thu, Apr 18, 2024 4:47 PM
OS/Arch:             darwin/arm64
Profile:             default
Server type:         <client error>

prefect server start

 ___ ___ ___ ___ ___ ___ _____
| _ \ _ \ __| __| __/ __|_   _|
|  _/   / _|| _|| _| (__  | |
|_| |_|_\___|_| |___\___| |_|

Configure Prefect to communicate with the server with:

    prefect config set PREFECT_API_URL=http://127.0.0.1:4200/api

View the API reference documentation at http://127.0.0.1:4200/docs

Check out the dashboard at http://127.0.0.1:4200



Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/__main__.py", line 4, in <module>
    uvicorn.main()
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/main.py", line 409, in main
    run(
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/main.py", line 575, in run
    server.run()
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/server.py", line 65, in run
    return asyncio.run(self.serve(sockets=sockets))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/asyncio/runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/asyncio/base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/server.py", line 69, in serve
    await self._serve(sockets)
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/server.py", line 76, in _serve
    config.load()
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/config.py", line 433, in load
    self.loaded_app = import_from_string(self.app)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/importer.py", line 22, in import_from_string
    raise exc from None
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/uvicorn/importer.py", line 19, in import_from_string
    module = importlib.import_module(module_str)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib._bootstrap>", line 1204, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1126, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1204, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1126, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1204, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 940, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/__init__.py", line 1, in <module>
    from . import models, orchestration, schemas, services
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/models/__init__.py", line 1, in <module>
    from . import (
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/models/agents.py", line 13, in <module>
    from prefect.server.database.dependencies import inject_db
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/database/dependencies.py", line 17, in <module>
    from prefect.server.database.interface import PrefectDBInterface
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/database/interface.py", line 9, in <module>
    from prefect.server.database.orm_models import BaseORMConfiguration
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/database/orm_models.py", line 22, in <module>
    from prefect.server.events.actions import ActionTypes
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/events/actions.py", line 79, in <module>
    from prefect.server.utilities.user_templates import (
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/prefect/server/utilities/user_templates.py", line 19, in <module>
    _template_environment = ImmutableSandboxedEnvironment(
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/jinja2/sandbox.py", line 253, in __init__
    super().__init__(*args, **kwargs)
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/jinja2/environment.py", line 363, in __init__
    self.extensions = load_extensions(self, extensions)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/jinja2/environment.py", line 117, in load_extensions
    extension = t.cast(t.Type["Extension"], import_string(extension))
                                            ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/minpark/mambaforge/envs/prefect/lib/python3.11/site-packages/jinja2/utils.py", line 149, in import_string
    return getattr(__import__(module, None, None, [obj]), obj)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ModuleNotFoundError: No module named 'jinja2_humanize_extension'
Server stopped!

Edit

pip seems to work.