Metaclass

met.py

from functools import wraps
from six import add_metaclass

class MetaCount(type):
    def __new__(cls, *args, **kwargs):
        obj = super(MetaCount, cls).__new__(cls, *args, **kwargs)
        obj.read_count = 0
        if hasattr(obj, 'read'):
            original_read = obj.read
            @wraps(original_read)
            def read_count(*args, **kwargs):
                obj.read_count += 1
                return original_read(*args, **kwargs)
            obj.read = read_count
        return obj


@add_metaclass(MetaCount)
class Toto(object):
    def read(self):
        """MyDoc."""
        return "Foo"

t = Toto()
t.read()
t.read()

assert "MyDoc" in t.read.__doc__
assert t.read_count == 2
assert t.read() == "Foo"
assert t.read_count == 3