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Under utils/common.py, 

TIMESTAMP_FORMAT_MILLIS = '%Y-%m-%dT%H:%M:%S.%fZ'

The %f produces time with microseconds, for example: 2020-03-18T19:43:18.115783Z.


However, when interacting the AWS s3 and sns apis, I receive DateTimes like this:

2020-03-02T22:32:13.240Z
i.e. milliseconds. 

This seems like a simple change to the utils. TIMESTAMP_FORMAT_MILLIS is named as if it should be millis as well. This is seems like a simple change. Is there a reason it should be microseconds?
return str(uuid.uuid4())[0:8]
def json_safe(item):
    """ return a copy of the given object (e.g., dict) that is safe for JSON dumping """
    try:
        return json.loads(json.dumps(item, cls=CustomEncoder))
    except Exception:
        item = fix_json_keys(item)
        return json.loads(json.dumps(item, cls=CustomEncoder))
def fix_json_keys(item):
    """ make sure the keys of a JSON are strings (not binary type or other) """
    item_copy = item
    if isinstance(item, list):
        item_copy = []
        for i in item:
            item_copy.append(fix_json_keys(i))
    if isinstance(item, dict):
        item_copy = {}
        for k, v in item.items():
            item_copy[to_str(k)] = fix_json_keys(v)
    return item_copy
def save_file(file, content, append=False):
    mode = 'a' if append else 'w+'
    if not isinstance(content, six.string_types):
        mode = mode + 'b'
    with open(file, mode) as f:
        f.write(content)
        f.flush()
def load_file(file_path, default=None, mode=None):