[Python] How to effectively use `repr()` vs `str()` for debugging and object representation in...

I'm learning more about Python's built-in functions and have come across repr(). I understand it's used to get a 'representation' of an object, but I'm a bit unclear on its practical use cases and how it differs from str().

Specifically, I'm looking for explanations and examples on:

1. Core Purpose: What is the primary intent or philosophy behind repr()? When would a developer typically use it?
2. Basic Data Types: How does repr() behave with common Python data types like strings, integers, lists, and dictionaries?
3. Custom Classes and __repr__: How do I implement the __repr__ special method in my own Python classes to control how my objects are represented?
4. repr() vs. str(): What are the key distinctions between repr() and str()? When should I prefer one over the other for debugging, logging, or user-facing output?

Any clear examples that illustrate these points would be extremely helpful! Thanks in advance.

• 
  What I tried:
  
  my_string = "hello"
  print(repr(my_string))
  
  my_list = [1, 2, 'three']
  print(repr(my_list))
  
  my_int = 123
  print(repr(my_int))
• 
  What I expected: For strings, I expected to see just hello (like print()). For lists and integers, I expected to see [1, 2, 'three'] and 123 respectively.
  
  
• 
  What actually resulted (Output):
  
  'hello'
  [1, 2, 'three']
  123

The string output ('hello') with quotes was a bit unexpected, as was the identical output for lists and integers compared to standard print(). This made me realize repr() isn't simply for printing, and there's a difference between it and str() or implicit printing. I'm looking to understand the significance of this difference and how to apply repr() effectively, especially with custom classes.

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