Testing whether Python's json module correctly outputs floating point numbers without loss of precision

float_test.py

import random
import json

digits = '0123456789'
for i in range(10000):
    ndigits = 10
    number = '0.' + ''.join([random.choice(digits) for j in range(ndigits)])
    number = number.rstrip('0')
    if number.endswith('.'): number += '0'
    json_number = json.dumps(float(number))
    try:
        assert (json_number == number)
    except AssertionError:
        if not ('e' in json_number and float(json_number) == float(number)):
            print 'Not the same:', number, float(number), json.dumps(float(number))