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PCAP – Certified Associate Python Programmer PCAP-31-03 · Domain 3: Strings

Indexing, negative indexing and slicing, including steps

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Last reviewed September 25, 2026 · Leer en español

A string is a sequence of characters, and each character has a position called an index. Indexes start at 0 for the first character. For s = 'Python', s[0] is 'P' and s[5] is 'n'. Using an index equal to or beyond the length, such as s[6], raises IndexError. Indexing always returns a string of length one, because Python has no separate character type.

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