How do I get a substring of a string in Python?

Slicing tips, tricks and pizzazz

Selective omission and copying strings

Want to omit certain characters like a master or copy an entire string like a pro? Use these nifty patterns:

substring = text[:-1]  # "I never liked the end anyway."
whole_string_copy = text[:]  # "One whole string to go, please!"
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With these techniques under your belt, you can trim prefixes or suffixes and even check for string equality with its slice copy—like checking if your haircut is symmetrical:

is_identical = x == x[:]  # "Mirror, mirror on the wall..."
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Shake it up: Reverse and skip

Want to stir things up a bit? Try reversing a string or selecting every nth character (e.g., alternate characters). It’s like a party trick, but with code:

reversed_string = text[::-1]  # "Whoa, I think that string just did a 180!"
alternate_characters = text[::2]  # "Every other character, step forward!"
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Precision slicing: Defining length

And for those who prefer precision, replicate the behavior of substring functions from other languages that use a start position and length.

substring = text[start:start + LENGTH]  # For when size matters
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Variables as indices? Why not!

Fancy dynamic substring extraction? Use variables as slice boundaries:

a, b = 2, 6  # "Meet start and end. They're variable."
substring = text[a:b]  # Slicing dynamics in action!
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Negative slicing: The end is just the beginning

Who said starting from the end isn't fashionable? Negative slicing lets you work with substrings relative to the end of the string:

trim_last_two = text[:-2]  # "The last two? Not a fan."
penultimate_character = text[-2]  # "The one before the last one? My favorite!"
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And, you can even do some backward extraction:

substring = text[-3:-1]  # "Just popping to the end for a sec!"
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Code with grace: Out-of-bound indices

Python slicing is all about grace under pressures like out-of-bounds indices; it doesn't break a sweat:

substring = text[2:100]  # "Even if you overshoot, I've got you covered."
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Efficient substring creation: Pro move

Slicing provides efficient substring creation and is highly favored by Python's optimized internals:

prefix_removed = text[1:]  # "First one out!"
suffix_removed = text[:-1]  # "And there goes the last one!"
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