.groupby() is a useful function to sort a dataframe into groups based on certain criteria. For example, if you have a dataframe of team rosters, you can group by team name or college and each group will consist only of entries with the same team or college.

#group by team
df.groupby(‘Team’)
#group by college
df.groupby(‘College’)
#group by team and college 
df.groupby([‘Team’, ‘College’])