Case Conversion

Python provides methods to change the case of strings. These are essential for normalizing user input and performing case-insensitive comparisons. lower() and upper() This prints "hello, world!", then "HELLO, WORLD!", then the original "Hello, World!". The original string is unchanged because strings are immutable in Python. Other Case Methods Python provides several case-related methods for different formatting needs: Case-Insensitive Comparing A common use case is comparing strings regardless of case. Try selecting different case methods below to see which ones produce a match: Checking Case You can check if a string is in a particular case: All three print True. These methods are useful for validation, such as checking if a username meets case requirements. Strings Are Immutable A funda

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