Human: how do you filter pandas dataframes by multiple columns Assistant: 
Here is some code to create dataframe `males` containing data of dataframe `df` where column `Gender` is equal to 'Male' and column `Year` is equal to 2014

males = df[(df[Gender] == 'Male') & (df[Year] == 2014)]

#Warning: this code generation is experimental. Please inspect the code for any bugs before executing.