Return a new PyLongObject based on the string value in
str, which is interpreted according to the radix in base.
If pend is non-NULL, *pend will point to the first
character in str which follows the representation of the
number. If base is 0, the radix will be determined base
on the leading characters of str: if str starts with
'0x' or '0X', radix 16 will be used; if str starts
with '0', radix 8 will be used; otherwise radix 10 will be
used. If base is not 0, it must be between 2 and
36, inclusive. Leading spaces are ignored. If there are no
digits, ValueError will be raised.