Compute a square root with math

Summary

Use the math module to compute a square root and handle invalid inputs.

Problem statement

Implement a function sqrt(n) that returns the square root of n using math.sqrt. If n is negative, return None. Accept integers and floats. For zero, return 0.0. For invalid types, raise a TypeError (natural behavior is acceptable), but typical numeric inputs should be handled.

Task

Write a function that returns the square root of a non-negative number using math.sqrt; return None for negative inputs.

Examples

Input format

Single numeric argument (int or float).

Output format

Return a float with the square root, or None for negative inputs.

Constraints

Use math.sqrt. Do not return complex numbers—return None instead for negatives.

Samples