Calling PyLong_FromString(str, NULL, 0) fails, if str is a string containing a decimal number with leading zeros, even though such strings should be parsed as decimal numbers according to the documentation:

"If base is 0, the radix will be determined based on the leading characters of str: if str starts with '0x' or '0X', radix 16 will be used; if str starts with '0o' or '0O', radix 8 will be used; if str starts with '0b' or '0B', radix 2 will be used; otherwise radix 10 will be used"

Examples:
PyLong_FromString("15", NULL, 0); // Returns int(15) (Correct)
PyLong_FromString("0xF", NULL, 0); // Returns int(15) (Correct)
PyLong_FromString("015", NULL, 0); // Should return int(15), but raises ValueError: invalid literal for int() with base 0: '015'

Version information:
Python 3.5.2 (v3.5.2:4def2a2901a5, Jun 25 2016, 22:18:55) [MSC v.1900 64 bit (AMD64)] on win32