how to add two dataframes together in pandas code example

Example 1: merge two dataframes based on column

df_outer = pd.merge(df1, df2, on='id', how='outer')

df_outer

Example 2: how to join two dataframe in pandas based on two column

merged_df = left_df.merge(right_df, how='inner', left_on=["A", "B"], right_on=["A2","B2"])