Write a dictionary with arrays as values into JSON format

[buran]

For completeness, let's add one more solution

spam = np.array([1, 2, 3])
eggs = {'some_key':spam}
print(eggs)
with open('export.json', 'w') as f:
    json.dump(eggs, f, separators=(',', ':'), sort_keys=True, indent=4, default=lambda x: x.tolist())
  
## to read it afterward
with open('export.json', "r") as f:
    data = json.load(f)
data = {key:np.array(value) for key, value in data.items()}
print(data)