[issue26983] float() can return not exact float instance

[Serhiy Storchaka]

Serhiy Storchaka added the comment:

Here is updated patch. Differences:

* Deprecation warning is now emitted in functions accepting floats (like math.sqrt).
* Improved error messages. Now reported wrong type name and a type of wrong __float__ method.
* float() now returns the same object for exact float argument.

Could you propose better warning message?

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue26983>
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