def validate_app_structure(value):
 try:
  if any(((int(v) < 0) for v in value.viewvalues())):
   raise ValueError(u'Must be greater than or equal to zero')
 except ValueError as err:
  raise ValidationError(err)

def validate_app_structure ( value ) : try : if any ( ( ( int ( v ) < 0 ) for v in value . viewvalues ( ) ) ) : raise ValueError ( u'Must be greater than or equal to zero' ) except ValueError as err : raise ValidationError ( err )
error if the dict values arent ints >= 0 .