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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?
cert = crypto.X509()
    subj = cert.get_subject()
    subj.C = 'AU'
    subj.ST = 'Some-State'
    subj.L = 'Some-Locality'
    subj.O = 'LocalStack Org'  
    subj.OU = 'Testing'
    subj.CN = 'localhost'
    
    
    serial_number = serial_number or 1001
    cert.set_version(2)
    cert.set_serial_number(serial_number)
    cert.gmtime_adj_notBefore(0)
    cert.gmtime_adj_notAfter(2 * 365 * 24 * 60 * 60)
    cert.set_issuer(cert.get_subject())
    cert.set_pubkey(k)
    alt_names = b'DNS:localhost,DNS:test.localhost.atlassian.io,IP:127.0.0.1'
    cert.add_extensions([
        crypto.X509Extension(b'subjectAltName', False, alt_names),
        crypto.X509Extension(b'basicConstraints', True, b'CA:false'),
        crypto.X509Extension(b'keyUsage', True, b'nonRepudiation,digitalSignature,keyEncipherment'),
        crypto.X509Extension(b'extendedKeyUsage', True, b'serverAuth')
    ])
    cert.sign(k, 'SHA256')
    cert_file = StringIO()
    key_file = StringIO()
    cert_file.write(to_str(crypto.dump_certificate(crypto.FILETYPE_PEM, cert)))
    key_file.write(to_str(crypto.dump_privatekey(crypto.FILETYPE_PEM, k)))
    cert_file_content = cert_file.getvalue().strip()