add mock packages in conf.py to fix documentation compilation

docs/source/conf.py

@@ -14,6 +14,7 @@
 #
 import os
 import sys
+from unittest.mock import MagicMock
 sys.path.insert(0, os.path.abspath('../../../'))
 
 # -- Project information -----------------------------------------------------
@@ -43,6 +44,16 @@
     'sphinx.ext.intersphinx',
 ]
 
+
+class Mock(MagicMock):
+    @classmethod
+    def __getattr__(cls, name):
+        return MagicMock()
+
+
+MOCK_MODULES = ['numpy', 'scipy']
+sys.modules.update((mod_name, Mock()) for mod_name in MOCK_MODULES)
+
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']