Python 3.1.1 string to hex

I am trying to use str.encode() but I get

>>> "hello".encode(hex)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: must be string, not builtin_function_or_method

I have tried a bunch of variations and they seem to all work in Python 2.5.2, so what do I need to do to get them to work in Python 3.1?

The hex codec has been chucked in 3.x. Use binascii instead:

>>> binascii.hexlify(b'hello')
b'68656c6c6f'

In Python 3.5+, encode the string to bytes and use the hex() method, returning a string.

s = "hello".encode("utf-8").hex()
s
# '68656c6c6f'

Optionally convert the string back to bytes:

b = bytes(s, "utf-8")
b
# b'68656c6c6f'

You've already got some good answers, but I thought you might be interested in a bit of the background too.

Firstly you're missing the quotes. It should be:

"hello".encode("hex")

Secondly this codec hasn't been ported to Python 3.1. See here. It seems that they haven't yet decided whether or not these codecs should be included in Python 3 or implemented in a different way.

If you look at the diff file attached to that bug you can see the proposed method of implementing it:

import binascii
output = binascii.b2a_hex(input)