Nicely pickling numpy array

myarray.py

import numpy as np
import pickle

class MyArray(np.ndarray):
    """An np.ndarray subclass with attrs that behave nicely."""
    def __new__(cls, a, meta=None):
        obj = np.asarray(a).view(cls)
        obj.meta = meta
        return obj

    def __array_finalize__(self, obj):
        if obj is None: return
        self.meta = getattr(obj, 'meta', None)
        if hasattr(obj, '__dict__'):
            for attr, val in obj.__dict__.items():
                setattr(self, attr, val)

    def __array_wrap__(self, out_arr, context=None):
        return np.ndarray.__array_wrap__(self, out_arr, context)

    def __reduce__(self):
        cons, args, state = super(MyArray, self).__reduce__()
        state = (state,) + (self.__dict__,)
        return (cons, args, state)

    def __setstate__(self, d):
        standard, extra = d
        super(MyArray, self).__setstate__(standard)
        for attr, val in extra.items():
            setattr(self, attr, val)

# An array that has an attribute
a = MyArray(np.array(range(5)), meta='meta_data')

# Can patch any other attributes
a.info = 'info_data'

# Pickling attributes works
b = pickle.loads(pickle.dumps(a))
print b, b.info, b.meta

# Attributes copied when ufunc applied
c = b + 1
print c, c.info, c.meta