Python panda merge is not working as expected

Panda merge is not working as expected

I am using this code

import pandas as pddata = {"Q1": [1, 2, 3, 4],"A2_1": [1, 2, 2, 1],"A2_2": [1, 1, 1, 1],"A2_3": [2, 2, 1, 1],"A2_4": [2, 2, 2, 1],"A3_1": [10, 25, 62, 18],"A3_2": [51, 51, 16, 17],"A3_3": [32, 23, 71, 31],"A3_4": [62, 52, 52, 11]}df = pd.DataFrame(data)# Melt DataFrame for A2melted_a2 = pd.melt(df, id_vars=["Q1"], value_vars=["A2_1", "A2_2", "A2_3", "A2_4"], var_name="A2", value_name="Value")# Melt DataFrame for A3melted_a3 = pd.melt(df, id_vars=["Q1"], value_vars=["A3_1", "A3_2", "A3_3", "A3_4"], var_name="A3", value_name="Value")# Merge melted DataFrames on 'Q1'result_df = pd.merge(melted_a2, melted_a3, on="Q1")# Drop unnecessary columnsresult_df.drop(columns=["A2", "A3"], inplace=True)print(result_df)

and my expectation for output is

however the real output is