Write to csv with Python

Purpose: Used when you want to write something in a text file, etc.

# 'w'about
('test.csv', 'w', encoding='utf-8')
Notation Overview
r Read
w Write new
a Write in postscript
r+ An error will occur if the additional write / read file does not exist.
w+ Create if there are no new write and read files
a+ Write and read additional notes, create if there is no file

Write with Hello World

hello.py



#
with open('test.csv', 'w', encoding='utf-8') as f:
    f.write('Hello World\n')

print('I wrote it.')



-----result------
I wrote it.

test.csv


Hellor World

Processing when outputting multiple lines

lang.py



lang = ['SQL',
        'Java',
        'Ruby',
        'PHP',
        'Python']

with open('lang.csv', 'w', encoding = 'utf-8') as f:
    for item in lang:
        f.write(item + '\n')
print('I wrote it.')

Execution result

lang.csv


SQL
Java
Ruby
PHP
Python

Applied date manipulation

time.py



from datetime import datetime

now = datetime.now()
#print(now) 2020-10-27 19:56:15.019242

str_now = f'{now:%Y/%m/%d %H:%M}'
#print(str_now) 2020/10/27 19:56

with open('time.csv', 'w', encoding='utf-8') as f:
    f.write(str_now + ' -holiday\n')

print('I wrote it.')


Execution result

time.csv



2020/10/27 20:00 -holiday

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