json for np.ndarray, range and Iterator

cio_dump.py

import numpy as np
import json 
from collections.abc import Iterator, Sequence

class CiOJSEncoderEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, np.ndarray):
            return obj.tolist()
        if isinstance(obj, np.generic):
            return obj.item()
        if isinstance(obj, Sequence) or isinstance(obj, Iterator):
            return list(obj)
            

        return json.JSONEncoder.default(self, obj)

a = np.array([[1, 2,  3], [4, 5, 6]])
json_dump = json.dumps({
    'a': a, 'aa': [2, (2, 3, 4), a],
    'bb': [2],
    'cc': range(5),
    'dd': map(lambda a: a**2, range(3))
    }, cls=CiOJSEncoderEncoder)
print(json_dump)