hide output to tidy up

Author: mmcky

lectures/inflation_history.md

@@ -20,12 +20,14 @@ Let's start by installing the necessary Python packages.
 The `xlrd` package is used by `pandas` to perform operations on Excel files.
 
 ```{code-cell} ipython3
+:tags: [hide-output]
 !pip install xlrd
 ```
 
 This lecture also requires `pandas >= 2.1.4`
 
 ```{code-cell} ipython3
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 from packaging.version import Version
 import pandas as pd
 if Version(pd.__version__) < Version('2.1.4'):