fix pip installs

Author: kp992

lectures/french_rev.md

@@ -62,8 +62,7 @@ This lecture uses data from three spreadsheets assembled by {cite}`sargent_velde
   * [datasets/assignat.xlsx](https://github.com/QuantEcon/lecture-python-intro/blob/main/lectures/datasets/assignat.xlsx)
 
 ```{code-cell} ipython3
-%pip install openpyxl
-%pip install requests
+!pip install openpyxl requests
 ```
 
 ```{code-cell} ipython3

lectures/heavy_tails.md

@@ -19,8 +19,7 @@ In addition to what's in Anaconda, this lecture will need the following librarie
 ```{code-cell} ipython3
 :tags: [hide-output]
 
-!pip install --upgrade yfinance pandas_datareader
-%pip install openpyxl
+!pip install yfinance pandas_datareader
 ```
 
 We use the following imports.

lectures/inequality.md

@@ -82,7 +82,6 @@ We will need to install the following packages
 :tags: [hide-output]
 
 !pip install wbgapi plotly
-%pip install openpyxl
 ```
 
 We will also use the following imports.

lectures/inflation_history.md

@@ -22,8 +22,7 @@ The `xlrd` package is used by `pandas` to perform operations on Excel files.
 ```{code-cell} ipython3
 :tags: [hide-output]
 
-!pip install xlrd
-!pip install openpyxl
+!pip install xlrd openpyxl
 ```
 
 <!-- Check for pandas>=2.1.4 for Google Collab Compat -->

lectures/long_run_growth.md

@@ -65,7 +65,7 @@ be interesting to describe both total GDP and GDP per capita as it evolves withi
 First we will need to install the following package
 
 ```{code-cell} ipython3
-%pip install openpyxl
+!pip install openpyxl
 ```
 
 Now let's import the packages needed to explore what the data says about long-run growth

lectures/mle.md

@@ -13,10 +13,6 @@ kernelspec:
 
 # Maximum Likelihood Estimation
 
-```{code-cell} ipython3
-%pip install openpyxl
-```
-
 ```{code-cell} ipython3
 from scipy.stats import lognorm, pareto, expon
 import numpy as np