[rjmorris]

The underscore is to avoid conflicts with your own attributes named make, asdict, etc. So you could do:

  MyClass = namedtuple("MyClass", ["make", "asdict", "fields"])
  x = MyClass(make=10, asdict=11, fields=12)
  print(x.asdict)

The "underscore-to-avoid-naming-conflicts" approach is used elsewhere in the Python standard library, too, although another example isn't coming to me at the moment.

[nerdponx]

Perhaps even weirder, the Enum class uses names like `_value_`. At one time, inventing nonstandard "magic method" names like `__value__` was considered off-limits, because in principle those names could later be used by the Python language spec itself. In practice, such additions have been very rare, and library authors have become a lot less squeamish about defining their own.

The core data model of "almost everything is a mutable lookup table" can be easy to work with and reason about at times, but sometimes it's a little too simple, and you end up with these kinds of ad-hoc and inconsistent workarounds even in the standard library.

[BerislavLopac]

That is correct, although I agree with the GP that it's a bit unclear. My preferred practice for this is to put the underscore at the end, so it would be make_ and asdict_