The things in Python you call types are traditionally referred to as tags. Tagged values are values of one type (the type in Python) but which can still be distinguished based on a run-time check of their tag.
Python only has one type. To quote from the article by professor Harper:
"And this is precisely what is wrong with dynamically typed languages: rather than affording the freedom to ignore types, they instead impose the bondage of restricting attention to a single type! Every single value has to be a value of that type, you have no choice! Even if in a particular situation we are absolutely certain that a particular value is, say, an integer, we have no choice but to regard it as a value of the “one true type” that is classified, not typed, as an integer."
Moreover, a tag is an implementation detail which rarely represents everything about a type.
E.g. a tag might tell us that some object is a function. But to know how many arguments it has, whether some are optional, and so on, we have to inspect fields beyond the tag.
