import bokeh's version from an internal util module (#5103)

.github/workflows/test.yml

@@ -97,6 +97,12 @@ jobs:
           eval "$(conda shell.bash hook)"
           conda activate test-environment
           conda install ${{ env.CHANS_DEV}} "freetype=2.10.4"
+      - name: Patch - do not install cffi 1.15.0 on macos and for python != 3.6
+        if: matrix.os == 'macos-latest' && matrix.python-version != '3.6'
+        run: |
+          eval "$(conda shell.bash hook)"
+          conda activate test-environment
+          conda install ${{ env.CHANS_DEV}} "cffi!=1.15.0"
       - name: doit env_capture
         run: |
           eval "$(conda shell.bash hook)"

holoviews/plotting/plot.py

@@ -43,7 +43,6 @@
     split_dmap_overlay, get_axis_padding, get_range, get_minimum_span,
     get_plot_frame, scale_fontsize, dynamic_update
 )
-from panel.util import bokeh_version
 
 class Plot(param.Parameterized):
     """
@@ -114,6 +113,7 @@ def document(self, doc):
             self.root is self.handles.get('plot') and
             not isinstance(self, GenericAdjointLayoutPlot)):
             doc.on_session_destroyed(self._session_destroy)
+            from .bokeh.util import bokeh_version
             if self._document and bokeh_version >= '2.4.0':
                 if isinstance(self._document.callbacks._session_destroyed_callbacks, set):
                     self._document.callbacks._session_destroyed_callbacks.discard(self._session_destroy)