[Python] How to set a column which suffix name is based on a value in another column

#Column X contains the suffix of one of V* columns. Need to put set column V{X} to 9 if X > 1.
#But my code created a new column 'VX' instead of updating one of the V* columns

import pandas as pd

df = pd.DataFrame({'EMPLID': [12, 13, 14, 15, 16, 17, 18],
'V1': [2,3,4,50,6,7,8],
'V2': [3,3,3,3,3,3,3],
'V3': [7,15,8,9,10,11,12],
'X': [2,3,1,3,3,1,2]
})

# Expected output:

# EMPLID V1 V2 V3 X
# 12 2 9 7 2
# 13 3 3 9 3
# 14 4 3 8 1
# 15 50 3 9 3
# 16 6 3 9 3
# 17 7 3 11 1
# 18 8 9 12 2


My code created a new column 'VX' instead of updating one of the V* columns:

df.loc[(df['X'] > 1), f"V{'X'}"] = 9


Any suggestion is appreciated. Thank you.

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