change sheetname to sheet_name because it's deprecated

Author: fkazemian

rst_files/_static/code/pandas/wb_download.py

@@ -9,7 +9,7 @@
     output.write(r.content)
 
 # == Parse data into a DataFrame == #
-govt_debt = pd.read_excel('gd.xls', sheetname='Data', skiprows=3, index_col=1)
+govt_debt = pd.read_excel('gd.xls', sheet_name='Data', skiprows=3, index_col=1)
 
 # == Take desired values and plot == #
 govt_debt = govt_debt.transpose()