Apply Custom Function

import pandas as pd
data = {
    'city' : ['Toronto', 'Montreal', 'Waterloo'],
    'points' : [80, 70, 90]
}
data
{'city': ['Toronto', 'Montreal', 'Waterloo'], 'points': [80, 70, 90]}

type(data)
dict

df = pd.DataFrame(data)
df
city points
0 Toronto 80
1 Montreal 70
2 Waterloo 90 
def get_bonus(x):
    if (x > 75):
        return x + 10
    return x
df['new_points'] = df['points'].apply(lambda x: get_bonus(x))
df['new_points']
0     90
1     70
2    100
Name: new_points, dtype: int64

df
city points new_points
0 Toronto 80 90
1 Montreal 70 70
2 Waterloo 90 100