In [1]: import app1.example                                                                                                                                                                                 

In [2]: app1.example.fix_polygon()                                                                                                                                                                          
version = 2.2.9
GEOS_NOTICE: Hole lies outside shell at or near point 1000 1000

p1.valid  = False
p1.valid_reason =  Hole lies outside shell[1000 1000]
mp.geom_type = MultiPolygon
mp.__class__ = <class 'django.contrib.gis.geos.polygon.Polygon'>
GEOS_ERROR: Argument is not a Polygon

---------------------------------------------------------------------------
GEOSException                             Traceback (most recent call last)
<ipython-input-2-82786a0572bd> in <module>
----> 1 app1.example.fix_polygon()

~/work/holebug/h1/app1/example.py in fix_polygon()
     15     print('mp.geom_type = {}'.format(mp.geom_type)) # MultiPolygon
     16     print('mp.__class__ = {}'.format(mp.__class__)) # returns Polygon in 2.2 MultiPolygon in 1.11
---> 17     print(len(mp))  # GESOEXception
     18 
     19 

~/.virtualenvs/hole111/lib/python3.6/site-packages/django/contrib/gis/geos/polygon.py in __len__(self)
     54     def __len__(self):
     55         "Return the number of rings in this Polygon."
---> 56         return self.num_interior_rings + 1
     57 
     58     @classmethod

~/.virtualenvs/hole111/lib/python3.6/site-packages/django/contrib/gis/geos/polygon.py in num_interior_rings(self)
    149         "Return the number of interior rings."
    150         # Getting the number of rings
--> 151         return capi.get_nrings(self.ptr)
    152 
    153     def _get_ext_ring(self):

~/.virtualenvs/hole111/lib/python3.6/site-packages/django/contrib/gis/geos/libgeos.py in __call__(self, *args, **kwargs)
    153 
    154     def __call__(self, *args, **kwargs):
--> 155         return self.func(*args, **kwargs)
    156 
    157     @cached_property

~/.virtualenvs/hole111/lib/python3.6/site-packages/django/contrib/gis/geos/prototypes/threadsafe.py in __call__(self, *args)
     45         # Call the threaded GEOS routine with the pointer of the context handle
     46         # as the first argument.
---> 47         return self.cfunc(self.thread_context.handle.ptr, *args)
     48 
     49     def __str__(self):

~/.virtualenvs/hole111/lib/python3.6/site-packages/django/contrib/gis/geos/prototypes/errcheck.py in check_minus_one(result, func, cargs)
     37     "Error checking on routines that should not return -1."
     38     if result == -1:
---> 39         raise GEOSException('Error encountered in GEOS C function "%s".' % func.__name__)
     40     else:
     41         return result

GEOSException: Error encountered in GEOS C function "GEOSGetNumInteriorRings_r".