Assign variable from Python wrapper

[lynnporu]

The following action needs to be possible:

print(lib.SOME_VARIABLE)  # undefined behaviour
lib.SOME_VARIABLE = 5
print(lib.SOME_VARIABLE)  # prints "5"

Where SOME_VARIABLE is the global variable defined in the dynamic library:

/* @variable SOME_VARIABLE
 * @type int
 */
int SOME_VARIABLE = 0;

The same behavior should be possible for globally defined structs.