pandas concat

pd.concat(objs, axis=0, join='outer', ignore_index=False, keys=None, levels=None, names=None, verify_integrity=False, sort=False, copy=True)

import pandas as pd

df1 = pd.DataFrame({'A': ['A0', 'A1', 'A2', 'A3'],
                    'B': ['B0', 'B1', 'B2', 'B3'],
                    'C': ['C0', 'C1', 'C2', 'C3'],
                    'D': ['D0', 'D1', 'D2', 'D3']},
                   index=[0, 1, 2, 3])

df2 = pd.DataFrame({'A': ['A4', 'A5', 'A6', 'A7'],
                    'B': ['B4', 'B5', 'B6', 'B7'],
                    'C': ['C4', 'C5', 'C6', 'C7'],
                    'D': ['D4', 'D5', 'D6', 'D7']},
                   index=[4, 5, 6, 7])

result = pd.concat([df1, df2])
print(result)

df3 = pd.DataFrame({'E': ['E0', 'E1', 'E2', 'E3'],
                    'F': ['F0', 'F1', 'F2', 'F3']},
                   index=[0, 1, 2, 3])

result = pd.concat([df1, df3], axis=1)
print(result)

result = pd.concat([df1, df3], axis=1, keys=['df1', 'df3'])
print(result)

result = pd.concat([df1, df2], ignore_index=True)
print(result)