What's the difference between str.isdigit(), isnumeric() and isdecimal() in Python?

When I run these methods

s.isdigit()
s.isnumeric()
s.isdecimal()

I always get as output either all True or all False for each value of s (which is a string). What's​ the difference between the three? Can you provide an example that gives two Trues and one False (or vice versa)?

It's mostly about unicode classifications. Here's some examples to show discrepancies:

>>> def spam(s):
...     for attr in 'isnumeric', 'isdecimal', 'isdigit':
...         print(attr, getattr(s, attr)())
...         
>>> spam('½')
isnumeric True
isdecimal False
isdigit False
>>> spam('³')
isnumeric True
isdecimal False
isdigit True

Specific behaviour is in the official docs here.

Script to find all of them:

import sys
import unicodedata
from collections import defaultdict

d = defaultdict(list)
for i in range(sys.maxunicode + 1):
    s = chr(i)
    t = s.isnumeric(), s.isdecimal(), s.isdigit()
    if len(set(t)) == 2:
        try:
            name = unicodedata.name(s)
        except ValueError:
            name = f'codepoint{i}'
        print(s, name)
        d[t].append(s)