Groupby only when certain conditional value exists in a column

Question

I have a df

Key1  Key2   Condition  Score
K11   K21     100        1000
K11   K21     200        3000
K11   K21     100        2000
K12   K22     100        12
K12   K22     200        133
K12   K22     100        300
K14   K24     100        144
K14   K24     200        122
K14   K24     100        4000

I want to do groupby for keys columns Key1 and Key2 only when Condition is 100 and find the max value of Score.

 df_trial=(df['Condition']=='100').groupby(['Key1','Key2'], as_index=False).max('Score')

This code doesnt seem to work and gives error. How can I achieve the desired output

Expected output

Key1  Key2   Condition  max_Score
K11   K21     100        2000
K12   K22     100        300
K14   K24     100        4000

Answer 1

This should work

import numpy as np
import pandas as pd


df = pd.DataFrame({'Key1': ['K11', 'K11', 'K11', 'K12', 'K12', 'K12', 'K14', 'K14', 'K14'],
          'Key2': ['K21', 'K21', 'K21', 'K22', 'K22', 'K22', 'K24', 'K24', 'K24'],
          'Condition': [100, 200, 100, 100, 200, 100, 100, 200, 100],
          'Score': [1000, 3000, 2000, 12, 133, 300, 144, 122, 4000]})

cond = df['Condition']==100
df_out = df.loc[cond].groupby(["Key1", "Key2"])['Score'].max().reset_index()
print(df_out)



   Key1 Key2  Score
0  K11  K21   2000
1  K12  K22    300
2  K14  K24   4000