Update README.md

Author: royjafari

README.md

@@ -58,7 +58,7 @@ We also provide a PDF file that has color images of the screenshots/diagrams use
 
 The code chunk under Chapter 5 Data Visualization, Subsection Example of comparing populations using boxplots (page 126) is misplaced. The correct chunk of code can be found on the dedicated GitHub of the book. Also, this is the correct code:
 
-`
+```
 income_possibilities = adult_df.income.unique()
 dataForBox_dic= {}
 for poss in income_possibilities:
@@ -68,7 +68,7 @@ for poss in income_possibilities:
 plt.boxplot(dataForBox_dic.values(),vert=False)
 plt.yticks([1,2],income_possibilities)
 plt.show()
-`
+```
 
 ## Get to Know the Author
 **Roy Jafari**