Bug: power() returns wrong result for negative exponents

[IYENTeam]

Bug Description

power(2, -3) returns 1.0 instead of 0.125.

Steps to Reproduce

from calculator import power

result = power(2, -3)
print(result)  # Expected: 0.125, Got: 1.0

Expected Behavior

power(2, -3) should return 0.125 (i.e., 2 ** -3).

Actual Behavior

Returns 1.0 because the for loop with range(-3) produces zero iterations.

Environment

• Python 3.x
• File: src/calculator.py