Bar graph from dataframe groupby

``` import pandas as pd import numpy as np import matplotlib.pyplot as plt df = pd.read_csv("arrests.csv") df = df.replace(np.nan,0) df = df.groupby(['home_team'])['arrests'].mean() ``` I'm trying to create a bar graph for dataframe. Under home_team are a bunch of team names. Under arrests are a number of arrests at each date. I've basically grouped the data by teams with the average arrests for that team. I'm trying to create a bar graph for this but am not sure how to proceed since one column doesn't have a header. Data ``` home_team,arrests Arizona,5.0 Arizona,6.0 Arizona,9.0 Arizona,6.0 Arizona,3.0 Arizona,4.0 Arizona,1.0 Arizona,4.0 Arizona,0.0 Arizona,12.0 Arizona,4.0 Arizona,1.0 Arizona,3.0 Arizona,7.0 Arizona,3.0 Arizona,7.0 Arizona,7.0 Arizona,3.0 Arizona,7.0 Arizona,2.0 Arizona,3.0 Arizona,2.0 Arizona,4.0 Arizona,7.0 Arizona,4.0 Arizona,6.0 Arizona,4.0 Arizona,2.0 Arizona,1.0 Arizona,6.0 Arizona,2.0 Arizona,4.0 Arizona,3.0 Arizona,10.0 Arizona,3.0 Arizona,2.0 Arizona,2.0 Arizona,0.0 Arizona,5.0 Arizona,2.0 Baltimore,1.0 Baltimore,0.0 Baltimore,0.0 Baltimore,0.0 Baltimore,2.0 Baltimore,0.0 Baltimore,0.0 Baltimore,0.0 Baltimore,3.0 Baltimore,1.0 Baltimore,0.0 Baltimore,3.0 Baltimore,5.0 Baltimore,0.0 Baltimore,8.0 Baltimore,0.0 Baltimore,4.0 Baltimore,5.0 Baltimore,0.0 Baltimore,0.0 Baltimore,0.0 Baltimore,1.0 Baltimore,0.0 Baltimore,0.0 Baltimore,3.0 Baltimore,0.0 Baltimore,6.0 Baltimore,0.0 Baltimore,0.0 Baltimore,0.0 Baltimore,4.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,2.0 Carolina,0.0 Carolina,1.0 Carolina,1.0 Carolina,1.0 Carolina,4.0 Carolina,1.0 Carolina,0.0 Carolina,0.0 Carolina,1.0 Carolina,1.0 Carolina,5.0 Carolina,1.0 Carolina,3.0 Carolina,3.0 Carolina,0.0 Carolina,2.0 Carolina,1.0 Carolina,1.0 Carolina,5.0 Carolina,1.0 Carolina,2.0 Carolina,1.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,0.0 Carolina,4.0 Carolina,6.0 Carolina,2.0 Carolina,3.0 Carolina,0.0 Carolina,3.0 Chicago,1.0 Chicago,0.0 Chicago,1.0 Chicago,0.0 Chicago,0.0 Chicago,0.0 Chicago,0.0 Chicago,1.0 Chicago,0.0 Chicago,1.0 Chicago,1.0 Chicago,0.0 Chicago,3.0 Chicago,1.0 Chicago,0.0 Chicago,2.0 Chicago,0.0 Chicago,0.0 Chicago,0.0 Chicago,2.0 Chicago,0.0 Chicago,2.0 Chicago,1.0 Chicago,2.0 Chicago,1.0 Chicago,1.0 Chicago,0.0 Chicago,2.0 Chicago,1.0 Chicago,0.0 Chicago,2.0 Chicago,1.0 Cincinnati,3.0 Cincinnati,0.0 Cincinnati,1.0 Cincinnati,2.0 Cincinnati,3.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,3.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,2.0 Cincinnati,4.0 Cincinnati,3.0 Cincinnati,3.0 Cincinnati,1.0 Cincinnati,3.0 Cincinnati,1.0 Cincinnati,0.0 Cincinnati,1.0 Cincinnati,0.0 Cincinnati,1.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,4.0 Cincinnati,0.0 Cincinnati,1.0 Cincinnati,1.0 Cincinnati,1.0 Cincinnati,10.0 Cincinnati,6.0 Cincinnati,0.0 Cincinnati,1.0 Cincinnati,1.0 Cincinnati,1.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,0.0 Cincinnati,0.0 Dallas,1.0 Dallas,1.0 Dallas,0.0 Dallas,1.0 Dallas,2.0 Dallas,0.0 Dallas,0.0 Dallas,0.0 Dallas,4.0 Dallas,6.0 Dallas,15.0 Dallas,0.0 Dallas,5.0 Dallas,15.0 Dallas,13.0 Dallas,0.0 Dallas,9.0 Dallas,0.0 Dallas,0.0 Dallas,0.0 Dallas,1.0 Dallas,8.0 Dallas,5.0 Dallas,9.0 Dallas,2.0 Dallas,7.0 Dallas,7.0 Dallas,3.0 Dallas,3.0 Dallas,2.0 Dallas,0.0 Dallas,1.0 Dallas,13.0 Dallas,3.0 Dallas,7.0 Dallas,8.0 Dallas,8.0 Dallas,5.0 Dallas,4.0 Dallas,1.0 Denver,2.0 Denver,0.0 Denver,0.0 Denver,0.0 Denver,2.0 Denver,0.0 Denver,0.0 Denver,0.0 Denver,4.0 Denver,1.0 Denver,4.0 Denver,0.0 Denver,0.0 Denver,0.0 Denver,3.0 Denver,0.0 Denver,5.0 Denver,8.0 Denver,11.0 Denver,5.0 Denver,2.0 Denver,5.0 Denver,1.0 Denver,3.0 Denver,1.0 Denver,1.0 Denver,7.0 Denver,6.0 Denver,6.0 Denver,1.0 Denver,4.0 Denver,7.0 Denver,3.0 Denver,2.0 Denver,0.0 Denver,4.0 Denver,3.0 Denver,3.0 Denver,1.0 Denver,0.0 Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Detroit, Green Bay,8.0 Green Bay,0.0 Green Bay,3.0 Green Bay,6.0 Green Bay,1.0 Green Bay,4.0 Green Bay,21.0 Green Bay,3.0 Green Bay,4.0 Green Bay,15.0 Green Bay,3.0 Green Bay,1.0 Green Bay,9.0 Green Bay,2.0 Green Bay,18.0 Green Bay,9.0 Green Bay,1.0 Green Bay,8.0 Green Bay,6.0 Green Bay,13.0 Green Bay,6.0 Green Bay,8.0 Green Bay,7.0 Green Bay,16.0 Green Bay,8.0 Green Bay,4.0 Green Bay,1.0 Green Bay,15.0 Green Bay,3.0 Green Bay,8.0 Green Bay,11.0 Green Bay,6.0 Green Bay,13.0 Green Bay,4.0 Green Bay,4.0 Green Bay,13.0 Green Bay,8.0 Green Bay,2.0 Green Bay,5.0 Green Bay,11.0 Houston,2.0 Houston,2.0 Houston,1.0 Houston,0.0 Houston,0.0 Houston,2.0 Houston,2.0 Houston,0.0 Houston,6.0 Houston,1.0 Houston,4.0 Houston,1.0 Houston,1.0 Houston,1.0 Houston,1.0 Houston,3.0 Houston,2.0 Houston,0.0 Houston,1.0 Houston,1.0 Houston,2.0 Houston,1.0 Houston,0.0 Houston,0.0 Houston,1.0 Houston,0.0 Houston,0.0 Houston,0.0 Houston,1.0 Houston,0.0 Houston,0.0 Houston,0.0 Houston,1.0 Houston,1.0 Houston,0.0 Houston,0.0 Houston,1.0 Houston,1.0 Houston,0.0 Houston,0.0 Indianapolis,2.0 Indianapolis,11.0 Indianapolis,0.0 Indianapolis,3.0 Indianapolis,0.0 Indianapolis,7.0 Indianapolis,0.0 Indianapolis,2.0 Indianapolis,1.0 Indianapolis,0.0 Indianapolis,3.0 Indianapolis,2.0 Indianapolis,4.0 Indianapolis,5.0 Indianapolis,1.0 Indianapolis,0.0 Indianapolis,0.0 Indianapolis,4.0 Indianapolis,2.0 Indianapolis,10.0 Indianapolis,1.0 Indianapolis,3.0 Indianapolis,0.0 Indianapolis,2.0 Indianapolis,4.0 Indianapolis,0.0 Indianapolis,0.0 Indianapolis,5.0 Indianapolis,3.0 Indianapolis,1.0 Indianapolis,4.0 Indianapolis,0.0 Indianapolis,3.0 Indianapolis,0.0 Indianapolis,2.0 Indianapolis,0.0 Indianapolis,2.0 Indianapolis,0.0 Indianapolis,3.0 Indianapolis,1.0 Jacksonville,4.0 Jacksonville,4.0 Jacksonville,2.0 Jacksonville,3.0 Jacksonville,1.0 Jacksonville,6.0 Jacksonville,3.0 Jacksonville,1.0 Jacksonville,5.0 Jacksonville,1.0 Jacksonville,2.0 Jacksonville,0.0 Jacksonville,0.0 Jacksonville,0.0 Jacksonville,1.0 Jacksonville,1.0 Jacksonville,3.0 Jacksonville,0.0 Jacksonville,2.0 Jacksonville,3.0 Jacksonville,3.0 Jacksonville,0.0 Jacksonville,1.0 Jacksonville,3.0 Jacksonville,3.0 Jacksonville,0.0 Jacksonville,3.0 Jacksonville,0.0 Jacksonville,0.0 Jacksonville,1.0 Jacksonville,1.0 Jacksonville,2.0 Jacksonville,0.0 Jacksonville,1.0 Jacksonville,0.0 Jacksonville,2.0 Jacksonville,2.0 Kansas City,0.0 Kansas City,1.0 Kansas City,2.0 Kansas City,3.0 Kansas City,1.0 Kansas City,0.0 Kansas City,2.0 Kansas City,2.0 Kansas City,0.0 Kansas City,0.0 Kansas City,0.0 Kansas City,4.0 Kansas City,0.0 Kansas City,1.0 Kansas City,1.0 Kansas City,0.0 Kansas City,4.0 Kansas City,4.0 Kansas City,0.0 Kansas City,2.0 Kansas City,3.0 Kansas City,4.0 Kansas City,4.0 Kansas City,0.0 Kansas City,1.0 Kansas City,5.0 Kansas City,2.0 Kansas City,1.0 Kansas City,2.0 Kansas City,5.0 Kansas City,8.0 Kansas City,3.0 Kansas City,2.0 Kansas City,0.0 Kansas City,1.0 Kansas City,0.0 Kansas City,1.0 Kansas City,0.0 Kansas City,2.0 Miami,1.0 Miami,4.0 Miami,0.0 Miami,3.0 Miami,0.0 Miami,4.0 Miami,2.0 Miami,5.0 Miami,3.0 Miami,0.0 Miami,0.0 Miami,0.0 Miami,4.0 Miami,3.0 Miami,1.0 Miami,3.0 Miami,2.0 Miami,4.0 Miami,4.0 Miami,5.0 Miami,4.0 Miami,1.0 Miami,2.0 Miami,7.0 Miami,5.0 Miami,1.0 Miami,1.0 Miami,2.0 Miami,2.0 Miami,0.0 Miami,1.0 New England,4.0 New England,6.0 New England,7.0 New England,2.0 New England,12.0 New England,6.0 New England,3.0 New England,1.0 New England,9.0 New England,6.0 New England,4.0 New England,5.0 New England,3.0 New England,7.0 New England,7.0 New England,2.0 New England,14.0 New England,1.0 New England,6.0 New England,1.0 New England,2.0 New England,4.0 New England,5.0 New England,4.0 New England,7.0 New England,7.0 New England,7.0 New England,6.0 New England,1.0 New England,2.0 New England,6.0 New England,2.0 New England,4.0 New England,0.0 New England,3.0 New England,6.0 New England,2.0 New England,9.0 New England,3.0 New England,2.0 New York Giants,18.0 New York Giants,15.0 New York Giants,19.0 New York Giants,23.0 New York Giants,26.0 New York Giants,35.0 New York Giants,31.0 New York Giants,21.0 New York Giants,39.0 New York Giants,6.0 New York Giants,12.0 New York Giants,16.0 New York Giants,20.0 New York Giants,23.0 New York Giants,14.0 New York Giants,15.0 New York Giants,21.0 New York Giants,12.0 New York Giants,19.0 New York Giants,29.0 New York Giants,16.0 New York Giants,46.0 New York Giants,29.0 New York Giants,10.0 New York Giants,16.0 New York Giants,22.0 New York Giants,24.0 New York Giants,20.0 New York Giants,23.0 New York Giants,33.0 New York Giants,9.0 New York Giants,28.0 New York Giants,18.0 New York Giants,24.0 New York Giants,26.0 New York Giants,35.0 New York Giants,22.0 New York Giants,39.0 New York Giants,31.0 New York Giants,14.0 New York Jets,34.0 New York Jets,23.0 New York Jets,28.0 New York Jets,20.0 New York Jets,30.0 New York Jets,12.0 New York Jets,14.0 New York Jets,31.0 New York Jets,22.0 New York Jets,18.0 New York Jets,15.0 New York Jets,10.0 New York Jets,16.0 New York Jets,38.0 New York Jets,11.0 New York Jets,18.0 New York Jets,17.0 New York Jets,22.0 New York Jets,20.0 New York Jets,29.0 New York Jets,11.0 New York Jets,26.0 New York Jets,8.0 New York Jets,10.0 New York Jets,12.0 New York Jets,27.0 New York Jets,22.0 New York Jets,18.0 New York Jets,25.0 New York Jets,14.0 New York Jets,20.0 New York Jets,28.0 New York Jets,7.0 New York Jets,26.0 New York Jets,28.0 New York Jets,15.0 New York Jets,44.0 New York Jets,27.0 New York Jets,30.0 New York Jets,32.0 Oakland,12.0 Oakland,15.0 Oakland,7.0 Oakland,12.0 Oakland,28.0 Oakland,15.0 Oakland,19.0 Oakland,19.0 Oakland,17.0 Oakland,25.0 Oakland,16.0 Oakland,17.0 Oakland,19.0 Oakland,7.0 Oakland,24.0 Oakland,8.0 Oakland,10.0 Oakland,15.0 Oakland,20.0 Oakland,14.0 Oakland,13.0 Oakland,20.0 Oakland,21.0 Oakland,10.0 Oakland,18.0 Oakland,30.0 Oakland,25.0 Oakland,49.0 Oakland,21.0 Oakland,11.0 Oakland,18.0 Oakland,21.0 Oakland,16.0 Oakland,22.0 Oakland,19.0 Oakland,15.0 Oakland,10.0 Philadelphia,2.0 Philadelphia,5.0 Philadelphia,5.0 Philadelphia,2.0 Philadelphia,2.0 Philadelphia,2.0 Philadelphia,1.0 Philadelphia,2.0 Philadelphia,2.0 Philadelphia,6.0 Philadelphia,1.0 Philadelphia,0.0 Philadelphia,4.0 Philadelphia,1.0 Philadelphia,1.0 Philadelphia,1.0 Philadelphia,2.0 Philadelphia,2.0 Philadelphia,1.0 Philadelphia,18.0 Philadelphia,3.0 Philadelphia,3.0 Philadelphia,10.0 Philadelphia,12.0 Philadelphia,3.0 Philadelphia,3.0 Philadelphia,1.0 Philadelphia,1.0 Philadelphia,1.0 Philadelphia,5.0 Philadelphia,2.0 Philadelphia,4.0 Philadelphia,5.0 Philadelphia,0.0 Philadelphia,2.0 Philadelphia,2.0 Philadelphia,0.0 Philadelphia,1.0 Philadelphia,5.0 Philadelphia,3.0 Pittsburgh,15.0 Pittsburgh,19.0 Pittsburgh,24.0 Pittsburgh,12.0 Pittsburgh,21.0 Pittsburgh,9.0 Pittsburgh,16.0 Pittsburgh,10.0 Pittsburgh,25.0 Pittsburgh,18.0 Pittsburgh,23.0 Pittsburgh,25.0 Pittsburgh,52.0 Pittsburgh,31.0 Pittsburgh,30.0 Pittsburgh,3.0 Pittsburgh,37.0 Pittsburgh,56.0 Pittsburgh,16.0 Pittsburgh,19.0 Pittsburgh,34.0 Pittsburgh,6.0 Pittsburgh,10.0 Pittsburgh,7.0 Pittsburgh,9.0 Pittsburgh,10.0 Pittsburgh,11.0 Pittsburgh,22.0 Pittsburgh,25.0 Pittsburgh,9.0 Pittsburgh,10.0 Pittsburgh,17.0 Pittsburgh,4.0 Pittsburgh,1.0 Pittsburgh,8.0 Pittsburgh,3.0 Pittsburgh,8.0 Pittsburgh,7.0 Pittsburgh,3.0 Pittsburgh,5.0 San Diego,15.0 San Diego,37.0 San Diego,29.0 San Diego,30.0 San Diego,69.0 San Diego,41.0 San Diego,30.0 San Diego,0.0 San Diego,23.0 San Diego,47.0 San Diego,45.0 San Diego,40.0 San Diego,31.0 San Diego,19.0 San Diego,12.0 San Diego,60.0 San Diego,29.0 San Diego,40.0 San Diego,13.0 San Diego,16.0 San Diego,24.0 San Diego,19.0 San Diego,36.0 San Diego,8.0 San Diego,20.0 San Diego,8.0 San Diego,18.0 San Diego,19.0 San Diego,19.0 San Diego,19.0 San Diego,17.0 San Diego,17.0 San Diego,18.0 San Diego,14.0 San Diego,13.0 San Diego,13.0 San Diego,17.0 San Diego,8.0 San Diego,14.0 San Diego,36.0 San Francisco,3.0 San Francisco,4.0 San Francisco,3.0 San Francisco,1.0 San Francisco,0.0 San Francisco,4.0 San Francisco,4.0 San Francisco,10.0 San Francisco,1.0 San Francisco,7.0 San Francisco,2.0 San Francisco,6.0 San Francisco,8.0 San Francisco,1.0 San Francisco,12.0 San Francisco,5.0 San Francisco,5.0 San Francisco,6.0 San Francisco,1.0 San Francisco,6.0 San Francisco,1.0 San Francisco,3.0 San Francisco,6.0 San Francisco,0.0 San Francisco,35.0 San Francisco,20.0 San Francisco,33.0 San Francisco,25.0 San Francisco,24.0 San Francisco,30.0 San Francisco,25.0 San Francisco,18.0 San Francisco,28.0 San Francisco,14.0 San Francisco,24.0 San Francisco,18.0 San Francisco,22.0 San Francisco,12.0 San Francisco,9.0 San Francisco,18.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,1.0 Seattle,0.0 Seattle,1.0 Seattle,0.0 Seattle,3.0 Seattle,2.0 Seattle,5.0 Seattle,1.0 Seattle,2.0 Seattle,4.0 Seattle,0.0 Seattle,2.0 Seattle,1.0 Seattle,0.0 Seattle,2.0 Seattle,0.0 Seattle,1.0 Seattle,1.0 Seattle,1.0 Seattle,0.0 Seattle,1.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,1.0 Seattle,0.0 Seattle,0.0 Seattle,1.0 Seattle,1.0 Seattle,1.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Seattle,0.0 Tampa Bay,0.0 Tampa Bay,2.0 Tampa Bay,1.0 Tampa Bay,1.0 Tampa Bay,2.0 Tampa Bay,2.0 Tampa Bay,2.0 Tampa Bay,1.0 Tampa Bay,2.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,1.0 Tampa Bay,2.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,2.0 Tampa Bay,0.0 Tampa Bay,2.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,2.0 Tampa Bay,1.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,0.0 Tampa Bay,0.0 Tampa Bay,0.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,0.0 Tampa Bay,1.0 Tampa Bay,1.0 Tennessee,0.0 Tennessee,0.0 Tennessee,0.0 Tennessee,0.0 Tennessee,1.0 Tennessee,0.0 Tennessee,1.0 Tennessee,2.0 Tennessee,0.0 Tennessee,1.0 Tennessee,3.0 Tennessee,0.0 Tennessee,0.0 Tennessee,0.0 Tennessee,4.0 Tennessee,0.0 Tennessee,1.0 Tennessee,0.0 Tennessee,0.0 Tennessee,3.0 Tennessee,0.0 Tennessee,3.0 Tennessee,7.0 Tennessee,0.0 Tennessee,0.0 Tennessee,6.0 Tennessee,8.0 Tennessee,0.0 Tennessee,1.0 Tennessee,0.0 Tennessee,2.0 Tennessee,3.0 Tennessee,8.0 Tennessee,3.0 Tennessee,3.0 Tennessee,4.0 Tennessee,7.0 Tennessee,0.0 Tennessee,0.0 Tennessee,12.0 Washington,1.0 Washington,2.0 Washington,1.0 Washington,2.0 Washington,7.0 Washington,0.0 Washington,2.0 Washington,2.0 Washington,5.0 Washington,3.0 Washington,3.0 Washington,2.0 Washington,5.0 Washington,5.0 Washington,4.0 Washington,7.0 Washington,7.0 Washington,2.0 Washington,1.0 Washington,3.0 Washington,4.0 Washington,2.0 Washington,0.0 Washington,7.0 Washington,2.0 Washington,3.0 Washington,0.0 Washington,4.0 Washington,0.0 Washington,3.0 Washington,5.0 Washington,1.0 Washington,0.0 Washington,0.0 Washington,1.0 Washington,2.0 Washington,2.0 Washington,2.0 Washington,4.0 Washington,1.0 ```