google / google/python-fire

Improve error message when required argument is missing

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Description

## Description
When a required function argument is not provided via the command line, Python Fire raises a generic TypeError that doesn't clearly indicate which argument is missing or how to provide it.

## Current Behavior
```bash
$ python my_script.py greet
TypeError: greet() missing 1 required positional argument: 'name'
```

## Expected Behavior
A more user-friendly error message that would guide the user:
```
$ python my_script.py greet
Error: Missing required argument 'name'
Usage: my_script.py greet
```

## Motivation
This would significantly improve the user experience, especially for new users who are unfamiliar with Python tracebacks. Clear error messages are crucial for CLI tools.

## Environment
- Python Fire version: 0.7.1
- Python version: 3.11
- OS: macOS

## Possible Solution
Catch TypeError exceptions in the argument parsing logic and check if they're related to missing arguments, then provide a more descriptive message with usage hints.

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