Mypy shows the error of an unsupported comparison operator but this class has `@functools.total_ordering`, `==` and `<`, so `<=` is implemented for this type.

money.py

import decimal
import functools
import typing


@functools.total_ordering
class Money:

    def __init__(self, amount: str) -> None:
        self.amount = decimal.Decimal(amount)

    def __eq__(self, other: typing.Any) -> bool:
        if isinstance(other, Money):
            return self.amount == other.amount
        return NotImplemented

    def __lt__(self, other: typing.Any) -> bool:
        if isinstance(other, Money):
            return self.amount < other.amount
        return NotImplemented


assert Money('10.00') <= Money('10.00')

mypy_output.txt

# mypy --strict money.py
money.py:23: error: Unsupported left operand type for <= ("Money")

setup.md

• Python 3.6.4
• mypy 0.570-dev-3545a71ba11576b08007f70d8407bf7924738886