Example of Table subclass helper for astropy. Uses our I3Table as an example.

i3table.py

import astropy.io.fits
import astropy.table
import astropy.io.registry


class I3Table(astropy.table.Table):
    """ Im3shape table class.  Same as a standard table except it supports
        attribute style column access ("table.e1") and does not try to print itself
        out when repr'd interactively.
    """
    def __getattr__(self, name):
        cols = self.__dict__['columns']
        if name in cols:
            return self[name]
        raise AttributeError("No property or column %s"%name)
    
    def __repr__(self):
        return "<im3shape catalog %d cols %d rows>" % (len(self.colnames), len(self))

    @classmethod
    def _construct_subclass_reader_wrapper(cls,function):
        def new_function(*args, **kwargs):
            return cls(function(*args,**kwargs))
        if function.__doc__:
            new_function.__doc__ = function.__doc__+"\nWrapped programmatically to return "+cls.__name__
        return new_function

    @classmethod
    def _register_subclass_io(cls,parent_class=astropy.table.Table):
        reader_registrations = []
        #Look at all the existing readers and if they are 
        #registered for the parent class then record the name
        #and function they use
        for (name,parent),reader in astropy.io.registry._readers.items():
            if parent_class==parent:
                reader_registrations.append((name,reader))
        #register all those functions for the new class too,
        #except that we need to wrap the function to return an instance
        #of our class instead
        for (name,reader) in reader_registrations:
            new_reader = cls._construct_subclass_reader_wrapper(reader)
            astropy.io.registry.register_reader(name, cls, new_reader)
        #Now do exactly the same for the writers, except no wrapping needed
        writer_registrations = []
        #Get existing
        for (name,parent),writer in astropy.io.registry._writers.items():
            if parent_class==parent:
                writer_registrations.append((name,writer))
        #register new
        for (name,writer) in writer_registrations:
            astropy.io.registry.register_writer(name, cls, writer)

I3Table._register_subclass_io()