Convert from ASCII string encoded in Hex to plain ASCII?

Understanding character encoding

At the root of it, ASCII and Unicode represent characters as numerical codes. In hexadecimal notation, an ASCII character corresponds to a byte, or two hex digits, like 68 for h.

Methods for Hex to ASCII conversion

Use the binascii module

When bytes.fromhex() feels too mainstream, there's always binascii.unhexlify():

import binascii
ascii_str = binascii.unhexlify("68656c6c6f").decode('ascii')  # hex to 'hello'
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Convert hex to integer manually

If you like living life in the fast lane and doing things manually, parse hex values and convert to ASCII characters:

ascii_str = ''.join(chr(int(''.join(pair), 16)) for pair in zip(*[iter("68656c6c6f")] * 2))  # 'cause who needs libraries, right?
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Decoding non-ASCII encodings

Sometimes, you stumble upon non-ASCII characters (they just like to stand out). Here’s how you handle them gracefully:

non_ascii = bytes.fromhex("e38182e38184e38186").decode('utf-8')  # hex to Japanese 'あいう', brings out your multilingual flair
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Explicit UTF-8 decoding respects multibyte characters.

Avoiding common pitfalls

Clean your hex input

Before anything, make sure your hex string is just hex, no spaces, no 0x - just pure unadulterated hexadecimal:

clean_hex = "68656C6C6F".replace(' ', '').lower().lstrip('0x')  # hex cleanup, because cleanliness is next to godliness
ascii_str = bytes.fromhex(clean_hex).decode('ascii')
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Python 2 method is deprecated

Once upon a time, in Python 2, .decode('hex') was the go-to method, but now it's time to move on and embrace Python 3.

Advanced hex conversions

• Why stop here? Let's explore the possibilities:

Functional programming style?

If you're into functional programming, this one's for you:

from functools import partial
hex_to_int = partial(int, base=16)  # you'll hex to the power of int
ascii_str = ''.join(map(chr, map(hex_to_int, ("68", "65", "6c", "6c", "6f")))) # because map() is the key to happiness
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No external libraries needed

Python's standard library is a treasure trove. You don't always need to venture out into the ocean of external libraries.

Readability over complexity

Above all, comprehensible code is key. Choose a method that makes your code readable and maintainable.