When two identical expressions are compared it is typically an indication of a mistake, since the Boolean value of the comparison will always be the same. Often, it can indicate that self has been omitted.

It is never good practice to compare a value with itself. If self has been omitted, then insert it. If the constant behavior is indeed required, use the Boolean literals True or False, rather than encoding them obscurely as x == x or similar.

Python Language Reference: Comparisons.