def printTraceback(self, file=None, elideFrameworkCode=False,
                       detail='default'):
        """
        Emulate Python's standard error reporting mechanism.

        @param file: If specified, a file-like object to which to write the
            traceback.

        @param elideFrameworkCode: A flag indicating whether to attempt to
            remove uninteresting frames from within Twisted itself from the
            output.

        @param detail: A string indicating how much information to include
            in the traceback.  Must be one of C{'brief'}, C{'default'}, or
            C{'verbose'}.
        """
        if file is None:
            from twisted.python import log
            file = log.logerr
        w = file.write

        if detail == 'verbose' and not self.captureVars:
            # We don't have any locals or globals, so rather than show them as
            # empty make the output explicitly say that we don't have them at
            # all.
            formatDetail = 'verbose-vars-not-captured'
        else:
            formatDetail = detail

        # Preamble
        if detail == 'verbose':
            w('*--- Failure #%d%s---\n' %
              (self.count,
               (self.pickled and ' (pickled) ') or ' '))
        elif detail == 'brief':
            if self.frames:
                hasFrames = 'Traceback'
            else:
                hasFrames = 'Traceback (failure with no frames)'
            w("%s: %s: %s\n" % (
                    hasFrames,
                    reflect.safe_str(self.type),
                    reflect.safe_str(self.value)))
        else:
            w('Traceback (most recent call last):\n')

        # Frames, formatted in appropriate style
        if self.frames:
            if not elideFrameworkCode:
                format_frames(self.stack[-traceupLength:], w, formatDetail)
                w("%s\n" % (EXCEPTION_CAUGHT_HERE,))
            format_frames(self.frames, w, formatDetail)
        elif not detail == 'brief':
            # Yeah, it's not really a traceback, despite looking like one...
            w("Failure: ")

        # Postamble, if any
        if not detail == 'brief':
            w("%s: %s\n" % (reflect.qual(self.type),
                            reflect.safe_str(self.value)))

        # Chaining
        if isinstance(self.value, Failure):
            # TODO: indentation for chained failures?
            file.write(" (chained Failure)\n")
            self.value.printTraceback(file, elideFrameworkCode, detail)
        if detail == 'verbose':
            w('*--- End of Failure #%d ---\n' % self.count)

        Emulate Python's standard error reporting mechanism.

        @param file: If specified, a file-like object to which to write the
            traceback.

        @param elideFrameworkCode: A flag indicating whether to attempt to
            remove uninteresting frames from within Twisted itself from the
            output.

        @param detail: A string indicating how much information to include
            in the traceback.  Must be one of C{'brief'}, C{'default'}, or
            C{'verbose'}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/failure.py