数据分析Pandas练习题五：合并

import numpy as np
import pandas as pd

raw_data_1 = {
    'subject_id': ['1', '2', '3', '4', '5'],
    'first_name': ['Alex', 'Amy', 'Allen', 'Alice', 'Ayoung'],
    'last_name': ['Anderson', 'Ackerman', 'Ali', 'Aoni', 'Atiches']
}

raw_data_2 = {
    'subject_id': ['4', '5', '6', '7', '8'],
    'first_name': ['Billy', 'Brian', 'Bran', 'Bryce', 'Betty'],
    'last_name': ['Bonder', 'Black', 'Balwner', 'Brice', 'Btisan']
}

raw_data_3 = {
    'subject_id': ['1', '2', '3', '4', '5', '7', '8', '9', '10', '11'],
    'test_id': [51, 15, 15, 61, 16, 14, 15, 1, 61, 16]