`pynput` related import failure

**Describe the bug**
Import is failing as follows (it may be related to this issue: https://github.com/moses-palmer/pynput/issues/420):
```
>>> from pandasgui import show
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
in
----> 1 from pandasgui import show

~/miniconda3/envs/py38/lib/python3.8/site-packages/pandasgui/__init__.py in
13
14 # Imports
---> 15 from pandasgui.gui import show
16
17 __all__ = ["show", "__version__"]

~/miniconda3/envs/py38/lib/python3.8/site-packages/pandasgui/gui.py in
15 from pandasgui.widgets.find_toolbar import FindToolbar
16 from pandasgui.widgets.json_viewer import JsonViewer
---> 17 from pandasgui.widgets.navigator import Navigator
18 from pandasgui.widgets.figure_viewer import FigureViewer
19 from pandasgui.widgets.settings_editor import SettingsEditor

~/miniconda3/envs/py38/lib/python3.8/site-packages/pandasgui/widgets/navigator.py in
22 return win32api.GetKeyState(0x01) not in [0, 1]
23 else:
---> 24 from pynput import mouse
25
26

~/miniconda3/envs/py38/lib/python3.8/site-packages/pynput/__init__.py in
38
39
---> 40 from . import keyboard
41 from . import mouse

~/miniconda3/envs/py38/lib/python3.8/site-packages/pynput/keyboard/__init__.py in
29
30
---> 31 backend = backend(__name__)
32 KeyCode = backend.KeyCode
33 Key = backend.Key

~/miniconda3/envs/py38/lib/python3.8/site-packages/pynput/_util/__init__.py in backend(package)
68 for module in modules:
69 try:
---> 70 return importlib.import_module('._' + module, package)
71 except ImportError as e:
72 errors.append(e)

~/miniconda3/envs/py38/lib/python3.8/importlib/__init__.py in import_module(name, package)
125 break
126 level += 1
--> 127 return _bootstrap._gcd_import(name[level:], package, level)
128
129

~/miniconda3/envs/py38/lib/python3.8/site-packages/pynput/keyboard/_darwin.py in
49 NSSystemDefined)
50
---> 51 from pynput._util.darwin import (
52 get_unicode_to_keycode_map,
53 keycode_context,

~/miniconda3/envs/py38/lib/python3.8/site-packages/pynput/_util/darwin.py in
58 OBJC = ctypes.PyDLL(objc._objc.__file__)
59
---> 60 OBJC.PyObjCObject_New.restype = ctypes.py_object
61 OBJC.PyObjCObject_New.argtypes = [ctypes.c_void_p, ctypes.c_int, ctypes.c_int]
62

~/miniconda3/envs/py38/lib/python3.8/ctypes/__init__.py in __getattr__(self, name)
392 if name.startswith('__') and name.endswith('__'):
393 raise AttributeError(name)
--> 394 func = self.__getitem__(name)
395 setattr(self, name, func)
396 return func

~/miniconda3/envs/py38/lib/python3.8/ctypes/__init__.py in __getitem__(self, name_or_ordinal)
397
398 def __getitem__(self, name_or_ordinal):
--> 399 func = self._FuncPtr((name_or_ordinal, self))
400 if not isinstance(name_or_ordinal, int):
401 func.__name__ = name_or_ordinal

AttributeError: dlsym(0x7fa65c2a9120, PyObjCObject_New): symbol not found
```

**Environment**
OS: OSX Big Sur 11.6
Python: 3.8.5
IDE: Jupyter

**Package versions**
```
hdijupyterutils==0.19.0
ipython @ file:///opt/concourse/worker/volumes/live/26969e8f-c9f7-42dc-6ffb-b3effd424c49/volume/ipython_1604101242376/work
ipython-genutils @ file:///tmp/build/80754af9/ipython_genutils_1606773439826/work
jupyter==1.0.0
jupyter-client @ file:///tmp/build/80754af9/jupyter_client_1601311786391/work
jupyter-console==6.4.0
jupyter-core @ file:///opt/concourse/worker/volumes/live/e8302867-5dbe-440b-7a37-f61bacc38ed8/volume/jupyter_core_1606148993907/work
jupyter-server==1.11.1
jupyter-server-proxy==3.1.0
jupyterlab==3.2.1
jupyterlab-pygments @ file:///home/conda/feedstock_root/build_artifacts/jupyterlab_pygments_1601375948261/work
jupyterlab-server==2.8.2
notebook @ file:///Users/runner/miniforge3/conda-bld/notebook_1605103840966/work
pandasgui @ git+https://github.com/adamerose/pandasgui.git@aa9c366882ec17dcf8531947631a602b486c9253
plotly==4.14.0
PyQt5==5.15.6
PyQt5-Qt5==5.15.2
PyQt5-sip==12.9.0
PyQtWebEngine==5.15.5
PyQtWebEngine-Qt5==5.15.2
```