'str' object has no attribute 'decode'. Python 3 error?

Here is my code:

import imaplib
from email.parser import HeaderParser

conn = imaplib.IMAP4_SSL('imap.gmail.com')
conn.login('[email protected]', 'password')
conn.select()
conn.search(None, 'ALL')
data = conn.fetch('1', '(BODY[HEADER])')
header_data = data[1][0][1].decode('utf-8')

at this point I get the error message

AttributeError: 'str' object has no attribute 'decode'

Python 3 doesn't have decode anymore, am I right? how can I fix this?

Also, in:

data = conn.fetch('1', '(BODY[HEADER])')

I am selecting only the 1st email. How do I select all?

You are trying to decode an object that is already decoded. You have a str, there is no need to decode from UTF-8 anymore.

Simply drop the .decode('utf-8') part:

header_data = data[1][0][1]

As for your fetch() call, you are explicitly asking for just the first message. Use a range if you want to retrieve more messages. See the documentation:

The message_set options to commands below is a string specifying one or more messages to be acted upon. It may be a simple message number ('1'), a range of message numbers ('2:4'), or a group of non-contiguous ranges separated by commas ('1:3,6:9'). A range can contain an asterisk to indicate an infinite upper bound ('3:*').

If you land here using jwt authentication after the PyJWT v2.0.0 release (22/12/2020), you might want to freeze your version of PyJWT to the previous release in your requirements.txt file.

PyJWT==1.7.1

Begining with Python 3, all strings are unicode objects.

  a = 'Happy New Year' # Python 3
  b = unicode('Happy New Year') # Python 2

The instructions above are the same. So I think you should remove the .decode('utf-8') part because you already have a unicode object.