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Strings & text

Format, split, join, parse, and clean text — everyday Python string patterns.

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Strings & text easy

How to Check if a String is Alphanumeric in Python

Uses the built-in str.isalnum() method to test whether a string contains only letters and numbers.

string alphanumeric validation
Python 
def is_alphanumeric(s: str) -> bool:
    return s.isalnum()

if __name__ == "__main__":
    test_cases = ["Hello123", "Hello World", "12345", "", "Hello@World", "Python3"]
    for case in test_cases:
        result = is_alphanumeric(case)
        print(f"{case!r:15} -> {result}")
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