A string conversion is an expression list enclosed in reverse (a.k.a. backward) quotes:
A string conversion evaluates the contained expression list and converts the resulting object into a string according to rules specific to its type.
If the object is a string, a number,
(In particular, converting a string adds quotes around it and converts ``funny'' characters to escape sequences that are safe to print.)
The built-in function repr() performs exactly the same conversion in its argument as enclosing it in parentheses and reverse quotes does. The built-in function str() performs a similar but more user-friendly conversion.
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