Typeerror:error when calling the Metaclass bases cannot create a consistent method resolution order (MRO) for bases A2, a 1 causes of occurrence and solutions

Originally wanted to test inheritance, there was this error:

Source

1 classA1 (object):2     deffo1 (self):3         Print "i ' m A1"4 classA2 (object):5     deffo1 (self):6         Print "i ' m A2"7 classB1 (A1,A2):8     defBar (self):9         Print "i ' m B1"Ten classB2 (A2,A1): One     defBar (self): A         Print "i ' m B2" - classC (B1,B2): #提示出现错误的地方 -     Pass the if __name__=='__main__': -m=C () -     PrintC.__mro__ - M.bar () +M.fo1 ()

The number of error rows appears in 13 lines, the actual composition of the time produced an error, (according to succession, a wide search composition)

At this point the composition is

Obviously cannot appear two A1, therefore may appear as above the error

B has a connection to a, only the following inheritance composition.

The code revision will be changed to

classA1 (object):deffo1 (self):Print "i ' m A1"classA2 (object):deffo1 (self):Print "i ' m A2"classB1 (A1,A2):defBar (self):Print "i ' m B1"classB2 (A1,A2):defBar (self):Print "i ' m B2"classC (B1,B2):Passif __name__=='__main__': M=C ()PrintC.__mro__M.bar () m.fo1 ( )

Typeerror:error when calling the Metaclass bases cannot create a consistent method resolution order (MRO) for bases A2, a 1 causes of occurrence and solutions