[Python-ideas] Hexadecimal floating literals

[Serhiy Storchaka]

The support of hexadecimal floating literals (like 0xC.68p+2) is 
included in just released C++17 standard. Seems this becomes a mainstream.

In Python float.hex() returns hexadecimal string representation. Is it a 
time to add more support of hexadecimal floating literals? Accept them 
in float constructor and in Python parser? And maybe add support of 
hexadecimal formatting ('%x' and '{:x}')?