Mastering Objectoriented Python
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The comparison operator methods

Python has six comparison operators. These operators have special method implementations. According to the documentation, the mapping works as follows:

  • x<y calls x.__lt__(y)
  • x<=y calls x.__le__(y)
  • x==y calls x.__eq__(y)
  • x!=y calls x.__ne__(y)
  • x>y calls x.__gt__(y)
  • x>=y calls x.__ge__(y)

We'll return to comparison operators again when looking at numbers in Chapter 7, Creating Numbers.

There's an additional rule regarding what operators are actually implemented that's relevant here. These rules are based on the idea that the object's class on the left defines the required special method. If it doesn't, Python can try an alternative operation by changing the order.