Update cloud-web-ipallocator.py

[Shantanuhatagale13]

Shebang updated for portability.
Exception handling now prints error details.
Used pop(0) for removing the first element from availIP. Added constants for better code management.
Used f-strings for modern string formatting.
File writing in with block for safety.
Improved comments to enhance readability.

Description

This PR...

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)
• build/CI
• test (unit or integration test code)

Feature/Enhancement Scale or Bug Severity

Feature/Enhancement Scale

• Major
• Minor

Bug Severity

• BLOCKER
• Critical
• Major
• Minor
• Trivial

Screenshots (if appropriate):

How Has This Been Tested?

How did you try to break this feature and the system with this change?

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