Remarks: O==object
2.Analysis of python-C3 algorithm:
#C3 Define the start of the reference
C3 Algorithm: The MRO is an ordered list L that is computed when the class is created.
L（Child（Base1，Base2）） = [ Child + merge（ L（Base1） , L（Base2） , Base1Base2 ）]
L（object） = [ object ]
Properties of L: The result is a list with at least one element in the list, the class itself.
E.g:
L(D) = L(D(O))
= D + merge (L (O))
= D + O
= [D,O]
L(B) = L(B(D,E))
= B + merge (L (D), L (E))
= B + merge(DO , EO) # The header D of the first list DO, other lists such as EO do not contain D at the end, so D can be brought up, that is, D is a legal header
= B + D + merge(O , EO) #The header is O from the first one, but the tail of the following list EO contains O, so O is illegal, so skip to the next list EO
= B + D + E + merge (O, O)
= [B,D,E,O]
Similarly:
L(C) = [C,E,F,O]
L(A(B,C)) = A + merge(L(B),L(C),BC)
= A + merge(BDEO,CEFO,BC)#B is a valid header
= A + B + merge(DEO,CEFO,C)#D is a valid header
= A + B + D + merge(EO,CEFO,C)#E is not a valid header, skip to the next list CEFO, at this time C is a valid header
= A + B + D + C + merge(EO,EFO)#Because C in the third list is deleted and empty, there is no third table, only two tables are left; E is legal at this time header
= A + B + D + C + E + merge(O,FO)#O is not a valid header, skip to the next list FO, F is a valid header,
= A + B + D + C + E + F + merge(O,O)#O is a valid header
= A + B + D + C + E + F + O
= [A,B,D,C,E,F,O]