An illustration of how Python multiple inheritance / mixins work. I always forget the order in which super() calls other methods.

mixins_demo.py

class CleanMixin(object):
    def clean(self):
        print "  clean() in CleanMixin"
        super(CleanMixin, self).clean()


class BaseClean(object):
    def clean(self):
        print "  clean() in BaseClean"


class BaseCleanCleanMixin(BaseClean, CleanMixin):
    pass


class CleanMixinBaseClean(CleanMixin, BaseClean):
    pass


class CustomCleanMixinBaseClean(CleanMixin, BaseClean):
    def clean(self):
        print "  clean() in CustomCleanMixinBaseClean"
        super(CustomCleanMixinBaseClean, self).clean()


print "class BaseCleanCleanMixin(BaseClean, CleanMixin)"
BaseCleanCleanMixin().clean()
print
print "class CleanMixinBaseClean(CleanMixin, BaseClean)"
CleanMixinBaseClean().clean()
print
print "class CustomCleanMixinBaseClean(CleanMixin, BaseClean)"
CustomCleanMixinBaseClean().clean()

"""
Output of this script looks like this:

class BaseCleanCleanMixin(BaseClean, CleanMixin)
  clean() in BaseClean

class CleanMixinBaseClean(CleanMixin, BaseClean)
  clean() in CleanMixin
  clean() in BaseClean

class CustomCleanMixinBaseClean(CleanMixin, BaseClean)
  clean() in CustomCleanMixinBaseClean
  clean() in CleanMixin
  clean() in BaseClean
"""