Error trap MPL versions

vendor_handler.ipynb

@@ -34,14 +34,10 @@
 
 if matplotlib.__version__.split('.')[0] < '3':
     raise ImportError('Requires matplotlib 3.0.0 or higher')
 ```
 
-%%%% Output: execute_result
-
-    True
-
 %% Cell type:markdown id: tags:
 
 ### In this case, the vendor also exports the data as an Excel file
 The Python `pandas` library allows easy import of Excel. The variable `df` is a Pandas dataframe.