how to set df value in filter code example

Example 1: pandas filter and change value

df.loc[df['dollars_spent'] > 0, 'purchase'] = 1

Example 2: filter df by column value

# does year equals to 2002?
# is_2002 is a boolean variable with True or False in it
>is_2002 =  gapminder['year']==2002
>print(is_2002.head())
0    False
1    False
2    False
3    False
4    False