Dot-access dictionary with default value

DefaultDotDict.py

#! /usr/bin/env python3
# 2019-12-28 Jani Tammi
#
#   Slightly improved DefaultDotDict, using '*' as default value.
#   NOTE:   DefaultDotDict.get('foobar') does NOT return value for key '*'.
#           You still get to define your own default value.
#


class DefaultDotDict(dict):
    """Dot-notation access dict with default key '*'. Returns value for key '*' for missing missing keys, or None if '*' value has not been set."""
    def __custom_get__(self, key):
        """For all DotDict.key access, missing or otherwise."""
        return self.get(key, self.get('*', None))
    __getattr__ = __custom_get__
    __setattr__ = dict.__setitem__
    __delattr__ = dict.__delitem__
    def __missing__(self, key):
        """For DefaultDotDict[key] access, missing keys."""
        return self.get('*', None)

a = DefaultDotDict(
    {
        'teacher': ['anyone', 'student', 'teacher'],
        'student': ['anyone', 'student'],
        '*': ['anyone']
    }
)
# Alternate create style
b = DefautlDotDict(
    teacher = ['anyone', 'student', 'teacher'],
    student = ['anyone', 'student']
)
# The clumsy thing is that you cannot create '*' key in the above, and need to do this separately:
b['*'] = ['anyone']

print("a.teacher            ", a.teacher)
print("a.student            ", a.student)
print("a.get('student')     ", a.get('student'))
print("a['student']         ", a['student'])
print("a.get('*')           ", a.get('*'))
print("a['*']               ", a['*'])
print("a['bozo']            ", a['bozo'])
print("a.bozo_the_clown     ", a.bozo_the_clown)
print("a.get('clown', ['!'])", a.get('clown', ['!']))

# EOF