Example of reflecting java.lang.System from docs doesnt work

[cmacdonald]

I have tried to implement the example of https://pyjnius.readthedocs.io/en/stable/api.html#jnius.JavaField

class System(JavaClass):
    __javaclass__ = 'java/lang/System'
    out = JavaField('()Ljava/io/InputStream;', static=True)

If I then do System().out, I get:

test_export_class.py:31: 
E   AttributeError: 'System' object has no attribute '__cls_storage'

If I then do System.out, I get:

jnius/jnius_export_class.pxi:455: in jnius.JavaField.__get__
E   TypeError: expected bytes, NoneType found

Do you want a PR with a unit test?

[gunaNeelamegam]

@cmacdonald
This would be the Signature for System Class.

 public static final java.io.PrintStream out;
    descriptor: Ljava/io/PrintStream;

Please try to use,

System = autoclass("java.lang.System")
class CustomSystem(System):
    __javaclass__ = "java/lang/System"

print(CustomSystem.out)