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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?
underscore_replacement = '---'
    meta_header_prefix = 'x-amz-meta-'
    prefix_len = len(meta_header_prefix)
    updated = False
    for key in list(request_headers.keys()):
        if key.lower().startswith(meta_header_prefix):
            key_new = meta_header_prefix + key[prefix_len:].replace('_', underscore_replacement)
            if key != key_new:
                request_headers[key_new] = request_headers.pop(key)
                updated = True
    if response:
        for key in list(response.headers.keys()):
            if key.lower().startswith(meta_header_prefix):
                key_new = meta_header_prefix + key[prefix_len:].replace(underscore_replacement, '_')
                if key != key_new:
                    response.headers[key_new] = response.headers.pop(key)
    return updated
def fix_creation_date(method, path, response):