human
Solve the following python programming problem given the following code:
def _ogrinspect(data_source, model_name, geom_name = 'geom', layer_key = 0, srid = None, multi_geom = False, name_field = None, imports = True, decimal = False, blank = False, null = False) : 
    '
    Helper routine for `ogrinspect` that generates GeoDjango models corresponding
    to the given data source.  See the `ogrinspect` docstring for more details.
    ' 
    if isinstance (data_source, str) : 
        data_source = DataSource (data_source) 
else : 
        if isinstance (data_source, DataSource) : 
            pass 
else : 
            raise TypeError ('Data source parameter must be a string or a DataSource object.') 
layer = data_source [layer_key] 
    ogr_fields = layer.fields 
    def process_kwarg(kwarg) : 
        if isinstance (kwarg, (list, tuple)) : 
            return [s.lower () for s in kwarg] 
else : 
            if kwarg : 
                return [s.lower () for s in ogr_fields] 
else : 
                return [] 
null_fields = process_kwarg (mfield) 
    blank_fields = process_kwarg (blank) 
    decimal_fields = process_kwarg (decimal) 
    def get_kwargs_str(field_name) : 
        kwlist = [] 
        if (field_name.lower () in null_fields) : 
            kwlist.append ('null=True') 
if (field_name.lower () in blank_fields) : 
            kwlist.append ('blank=True') 
if kwlist : 
            return (', ' + ', '.join (kwlist)) 
else : 
            return '' 
if imports : 
        (yield '# This is an auto-generated Django model module created by ogrinspect.') 
        (yield 'from django.contrib.gis.db import models') 
        (yield '') 
(yield ('class %s(models.Model):' % model_name)) 
    for (field_name, width, precision, field_type) in izip (ogr_fields, layer.field_widths, layer.field_precisions, layer.field_types) : 
        mfield = field_name.lower () 
        if (mfield [(- 1) :] == '_') : 
            mfield += 'field' 
kwargs_str = get_kwargs_str (field_name) 
        if (field_type is OFTReal) : 
            if (field_name.lower () in decimal_fields) : 
               ...

    
    

    Fix the buggy line: null_fields = process_kwarg (mfield)
assistant
#Here is Python program to fix the buggy line: null_fields = process_kwarg (mfield)
.

null_fields = process_kwarg (null)