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Validate password strength rules

Check password strength according to multiple rules and return a boolean.

Python practice17 minError Handling & Edge CasesIntermediateLast updated March 20, 2026

Problem statement

Create is_strong_password(password) -> bool that returns True if the password meets all of the following requirements, otherwise False: - Minimum length: 8 characters. - Contains at least one uppercase ASCII letter. - Contains at least one lowercase ASCII letter. - Contains at least one digit. - Contains at least one special character from the set: !@#$%^&*()-_+= - Does not contain any whitespace characters. - Is not one of a short list of common insecure passwords (e.g., 'password', '12345678', 'qwerty'). Function must handle non-string inputs by returning False and must not raise exceptions on unexpected inputs.

Task

Implement a password validator that enforces length, character variety, and common-password avoidance.

Examples

Valid password

Input

is_strong_password('Aa1!abcd')

Output

True

Meets length and contains uppercase, lowercase, digit, and special char.

Too weak

Input

is_strong_password('weakpass')

Output

False

Missing digit, uppercase and special character.

Input format

A single argument: password (expected string).

Output format

Return True if password is strong, otherwise False.

Constraints

- Only ASCII checks for letter/digit classification. - No external libraries. - Keep the common-password list short but reasonable.

Samples

Sample 1

Input

is_strong_password('Password1!')

Output

True

Typical acceptable strong password.