How do I reverse a string in Python?

Understanding string slicing

Python slicing uses the format start:stop:step, allowing powerful manipulation of strings. Employ a negative step (-1) to reverse a sequence. With start and stop omitted, it operates on the entire string.

# Beer gone in reverse! "🍺"[::-1]
reversed_beer = my_string[::-1]
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Slicing allows precise results. Need only a portion? Specify start and stop:

# Hey there, opposite day! "hey there"[5:2:-1]
opposite_day = my_string[5:2:-1]
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Other ways to reverse strings

While [::-1] is quick and "pythonic", other methods might improve readability or address specific situations:

Using reversed() function

reversed() gives an iterator in reversed order. Use ''.join() to get a string:

# Turtles, but in reverse
reversed_turtles = ''.join(reversed(my_string))  # "Shell yeah!" reversed
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Encapsulating slice in function

A quick slice muffled inside a function boosts readability and reuse:

# Gift wrap the magic!
def reversible_string(a_string):
    return a_string[::-1]

print(reversible_string('lap'))  # Should print... take a guess!
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Functions: because some operations love to play hard-to-get.

join with list comprehension

Blend join() and a list comprehension for adaptable handling:

# Let's do-it-yourself
reversed_diy = ''.join([char for char in reversed(my_string)])  # Craftsman mode: ON
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Master slice notation

Mastering slice notation is as crucial as avoiding pineapples on pizza. With negative indexes, you can reference from the string's end:

# Detective mode, last three clues, in reverse!
last_three = my_string[:-4:-1]
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Remember: stop is exclusive; start is inclusive. Python follows a strict bouncer policy.

Unicode and emojis

Unicode strings with emojis or compound characters? Pfft, grapheme library's got you covered:

import grapheme

# Make emojis moonwalk
reversed_unicode_str = grapheme[::-1](my_string)  # Even emojis have a backside
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Speed is key

Performance mattering more than a pizza delivery? Benchmark the options:

import timeit

# Ready, set, go!
slicing_time = timeit.timeit(lambda: my_string[::-1], number=1000)
reversed_time = timeit.timeit(lambda: ''.join(reversed(my_string)), number=1000)

print(f"Slicing: {slicing_time}, Reversed: {reversed_time}")  # Let's see who wins
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Strings are immutable, remember?

Python strings don't evolve like Pokémon. Avoid character-by-character construction — it's the Snorlax of string operations.