How Does Python's `repr()` Function Differ from `str()`, and Why Are Double Quotes Added to its Output?

Understanding the repr( ) Function in Python

repr( ) provides an evaluatable string representation of an object in Python. It returns a string that can be evaluated using the eval( ) function, resulting in the same object.

Questions and Answers:

1. Why are double quotes added to the output of repr(x)?

repr( ) encompasses the string representation of an object with double quotes to represent a string literal that can be evaluated by eval( ). In contrast, str( ) does not add quotes because it returns the string representation without evaluating it.

2. Why does eval("'foo'") return 'foo' instead of the object x that was initially assigned to it?

eval( ) takes a string as input and evaluates it. When you call eval("'foo'"), it interprets the contents of the string and returns 'foo' directly, bypassing the object assignment that was done with x. To evaluate the object itself, you would need to pass x as the argument to eval( ).

Additional Insights:

• repr( ) is useful for providing a string representation that can be used to reconstruct the object later.
• The eval( ) function is typically used to execute code dynamically at runtime.
• str( ) simply returns the string representation of an object without evaluating it.
• Objects in Python have magic methods like repr and __str__, which customize the string and representation of the object.

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