pandas merging section code example
Example 1: combining 2 dataframes pandas
df_3 = pd.concat([df_1, df_2])
Example 2: python dataframe left join
>>> left.merge(right, on='user_id', how='left')
df_3 = pd.concat([df_1, df_2])
>>> left.merge(right, on='user_id', how='left')