컬럼에 여러 값들이 있을 때 중복되는 데이터 없이 어떤 데이터들이 있는지 확인하는 방법

import pandas as pd
import numpy as np
from pandas import Series
from pandas import DataFrame

job_list = [{'name': 'John', 'job': "teacher"},
                {'name': 'Nate', 'job': "teacher"},
                {'name': 'Fred', 'job': "teacher"},
                {'name': 'Abraham', 'job': "student"},
                {'name': 'Brian', 'job': "student"},
                {'name': 'Janny', 'job': "developer"},
                {'name': 'Nate', 'job': "teacher"},
                {'name': 'Obrian', 'job': "dentist"},
                {'name': 'Yuna', 'job': "teacher"},
                {'name': 'Rob', 'job': "lawyer"},
                {'name': 'Brian', 'job': "student"},
                {'name': 'Matt', 'job': "student"},
                {'name': 'Wendy', 'job': "banker"},
                {'name': 'Edward', 'job': "teacher"},
                {'name': 'Ian', 'job': "teacher"},
                {'name': 'Chris', 'job': "banker"},
                {'name': 'Philip', 'job': "lawyer"},
                {'name': 'Janny', 'job': "basketball player"},
                {'name': 'Gwen', 'job': "teacher"},
                {'name': 'Jessy', 'job': "student"}
         ]

df = pd.DataFrame(job_list, columns = ['name', 'job'])

df
       name                job
0      John            teacher
1      Nate            teacher
2      Fred            teacher
3   Abraham            student
4     Brian            student
5     Janny          developer
6      Nate            teacher
7    Obrian            dentist
8      Yuna            teacher
9       Rob             lawyer
10    Brian            student
11     Matt            student
12    Wendy             banker
13   Edward            teacher
14      Ian            teacher
15    Chris             banker
16   Philip             lawyer
17    Janny  basketball player
18     Gwen            teacher
19    Jessy            student

• unique()

df.job.unique()
array(['teacher', 'student', 'developer', 'dentist', 'lawyer', 'banker',
       'basketball player'], dtype=object)

컬럼에 해당하는 값들을 중복되지 않게 한번만 출력한다.

• value_counts()

df.job.value_counts()
teacher              8
student              5
lawyer               2
banker               2
developer            1
dentist              1
basketball player    1
Name: job, dtype: int64

각 데이터들에 해당하는 값이 몇개가 있는지 출력하는 함수