How to check if the values of a message are changing [closed]

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I have a parameter message accompanying images. This message is mostly constant unless there is a change in the configuration. However the header is changing as time goes by. Is it possible to compare the current and the previous message without actually comparing each components of the message in python?

For instance, considering

message1.header = header1
message1.B = b
message1.C = c
message1.D = d

message2.header = header2
message2.A = a
message2.B = b
message2.C = c

message3.header = header
message3.A = d
message3.B = b
message3:C = c

message1 and message2 are the same while message3 is different.