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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?
ident = self._ident()
        removed = self.CONTEXTS_BY_THREAD.pop(ident, None)
        if not self.CONTEXTS_BY_THREAD:
            
            self._set(self.orig_stdout, self.orig_stderr, self.orig___stdout, self.orig___stderr)
        
        removed._stdout.flush()
        removed._stderr.flush()
        out = removed._stdout.getvalue()
        err = removed._stderr.getvalue()
        
        removed._stdout.close()
        removed._stderr.close()
        removed._stdout = out
        removed._stderr = err
    def _set(self, out, err, __out, __err):
        sys.stdout, sys.stderr, sys.__stdout__, sys.__stderr__ = (out, err, __out, __err)
    def _proxy(self, original_stream, type):
        def proxy():
            ident = self._ident()
            ctx = self.CONTEXTS_BY_THREAD.get(ident)
            if ctx:
                return ctx._stdout if type == 'stdout' else ctx._stderr
            return original_stream
        return proxy
    def _ident(self):