Fix SyntaxError and improve celsius_to_fahrenheit function in python/simple_utils.py

[coderabbitai]

Problem Description

The celsius_to_fahrenheit function in python/simple_utils.py has several issues that need to be addressed:

1. SyntaxError: Missing indentation in the function body causing a syntax error
2. Missing type hints: Function lacks proper type annotations for parameters and return value
3. Missing docstring: No documentation explaining the function's purpose, parameters, and return value
4. Inconsistent return type: Should ensure consistent float return type

Context

This issue was identified during code review of PR #41.

Related Links:

• PR: Hamidbranch #41
• Comment: Hamidbranch #41 (comment)

Requested by: @outlookhammer