Dl objects, as returned by open() above, have the following methods:
None. This is useful in code like:
>>> if a.sym('time'): ... a.call('time') ... else: ... time.time()
(Note that this function will return a non-zero number, as zero is the NULL pointer)
None, which will be passed as NULL. Note that strings should only be passed to functions as const char*, as Python will not like its string mutated.
There must be at most 10 arguments, and arguments not given will be
None. The function's return value must be a C
long, which is a Python integer.