Change Date Formats in CSV With Python 3

How can I change date format in csv in Python 3

Suppose you have a date x:

x = "2017-07-01T15:55Z"

You can convert it into a datetime.datetime with your formate %Y-%m-%dT%H:%MZ:

from datetime import datetime
d = datetime.strptime(x, '%Y-%m-%dT%H:%MZ')

Then format it:

d.strftime("%m/%d/%Y")

You'll get:

'07/01/2017'

The complete code is:

from datetime import datetime
x = "2017-07-01T15:55Z"
x = datetime.strptime(x, '%Y-%m-%dT%H:%MZ').strftime("%m/%d/%Y")

======= EDIT =======

For your follow up question:
you need to change row after formatting ts:

ts = row[17]
ts = datetime.strptime(ts, '%Y-%m-%dT%H:%MZ').strftime("%m/%d/%Y")
if ts != "":
    row[17] = ts # this is what you miss
    writer.writerow(row)

Change date formats in csv with Python 3

import csv
import re
from datetime import datetime

lines = []
# open file as read-only
with open('partner_new_testteam.csv', "r", newline='') as data:
    reader = csv.reader(data)
    # go over all of its rows, and the row's items and change 
    # items that match the date format
    for row in reader:
        for i, string in enumerate(row):
            if re.match(r"\d+\/\d+\/\d+", string):
                datetimeobject = datetime.strptime(string, '%d/%m/%Y')
                new_string = datetimeobject.strftime('%Y-%m-%d')
                row[i] = new_string
                print("Replaced", string, "with", new_string)
        # save edited, and originally correct ones to new list
        new_row = row
        lines.append(new_row)

# write new rows by overwriting original file
with open('partner_new_testteam.csv', "w", newline='') as data:
    writer = csv.writer(data)
    writer.writerows(lines)

Your current code does not actually change anything. You never replaced anything and you didn't open the file with write access.

You also should not use try: like it is an if. The regex matches x/x/x, where x is any amount of numbers.

Dealing with different date formats in python

Try it one way, and if it doesn't work, try it the other way.

try:
    df['Appointment Date'] = pd.to_datetime(df['Appointment Date'], format="%d/%m/%Y/%H:%M:%S").dt.strftime("%d/%m/%Y")
except WhateverDateParseException:
    df['Appointment Date'] = pd.to_datetime(df['Appointment Date'], format="%Y/%m/%d/%H:%M:%S").dt.strftime("%d/%m/%Y")

Of course, instead of WhateverDateParseException use the actual exception that is raised in your code.

Edit: fixed missing "%S"

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