diff --git a/doc/requirements.txt b/doc/requirements.txt
index 9dd0319ffe..5c4ee63947 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -37,5 +37,5 @@ orjson
 dash-bio
 jinja2<3.1
 parmed<=3.4.4; python_version<"3.8"
+dask==2022.2.0
 polars
-dask==2022.2.0
\ No newline at end of file
diff --git a/packages/python/plotly/_plotly_utils/optional_imports.py b/packages/python/plotly/_plotly_utils/optional_imports.py
index 32dec4e12a..a31e087a34 100644
--- a/packages/python/plotly/_plotly_utils/optional_imports.py
+++ b/packages/python/plotly/_plotly_utils/optional_imports.py
@@ -2,6 +2,7 @@
 Stand-alone module to provide information about whether optional deps exist.
 
 """
+
 from importlib import import_module
 import logging
 import sys
@@ -19,10 +20,9 @@ def get_module(name, should_load=True):
     :return: (module|None) If import succeeds, the module will be returned.
 
     """
-    if name in sys.modules:
-        return sys.modules[name]
     if not should_load:
-        return None
+        return sys.modules.get(name, None)
+
     if name not in _not_importable:
         try:
             return import_module(name)
@@ -32,3 +32,5 @@ def get_module(name, should_load=True):
             _not_importable.add(name)
             msg = f"Error importing optional module {name}"
             logger.exception(msg)
+
+    return None
diff --git a/packages/python/plotly/test_requirements/requirements_38_core.txt b/packages/python/plotly/test_requirements/requirements_38_core.txt
index edb622db5c..61bfc653cd 100644
--- a/packages/python/plotly/test_requirements/requirements_38_core.txt
+++ b/packages/python/plotly/test_requirements/requirements_38_core.txt
@@ -1,3 +1,3 @@
 requests==2.25.1
 tenacity==6.2.0
-pytest==6.2.3
+pytest==8.1.1
diff --git a/packages/python/plotly/test_requirements/requirements_38_optional.txt b/packages/python/plotly/test_requirements/requirements_38_optional.txt
index e1c0c56b38..4eed0bb5e6 100644
--- a/packages/python/plotly/test_requirements/requirements_38_optional.txt
+++ b/packages/python/plotly/test_requirements/requirements_38_optional.txt
@@ -5,7 +5,7 @@ numpy==1.20.2
 xarray==0.17.0
 statsmodels
 Pillow==8.2.0
-pytest==6.2.3
+pytest==8.1.1
 pytz==2021.1
 ipython[all]==7.22.0
 ipywidgets==8.0.2