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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def calc_widths_filter(self, next_filter):
 """ Coroutine to analyze the incoming data stream for creating optimal column width choices. This may buffer some of the incoming stream if there isn't enough information to make good choices about column widths. Also it may resize widths if certain conditions are met such as the terminal width resize event being detected. """

        window_sent = not not self.data_window
        next_primed = False
        genexit = None
        if not self.data_window:
            start = time.monotonic()
            while len(self.data_window) < self.min_render_prefill or \
                (len(self.data_window) < self.max_render_prefill and
                 (time.monotonic() - start) < self.max_render_delay):
                try:
                    self.data_window.append((yield))
                except GeneratorExit as e:
                    genexit = e
                    break
        while True:
            if self.width != self.desired_width:
                self.headers_drawn = False  # TODO: make optional
                self.width = self.desired_width
                remaining = self.usable_width
                widths = [x['width'] for x in self.colspec]
                preformatted = [i for i, x in enumerate(self.colspec)
                                if x['overflow'] == 'preformatted']
                unspec = []
                for i, width in enumerate(widths):
                    fixed_width = self.width_normalize(width)
                    if fixed_width is None:
                        unspec.append(i)
                    else:
                        widths[i] = fixed_width
                        remaining -= fixed_width
                if unspec:
                    if self.table.flex and self.data_window:
                        for i, w in self.calc_flex(self.data_window, remaining,
                                                   unspec, preformatted):
                            widths[i] = w
                    else:
                        dist = self._uniform_dist(len(unspec), remaining)
                        for i, width in zip(unspec, dist):
                            widths[i] = width
                self.widths = widths
                self.formatters = self.make_formatters()
            if not next_primed:
                next(next_filter)
                next_primed = True
            if not window_sent:
                for x in self.data_window:
                    next_filter.send(x)
                window_sent = True
            if genexit:
                raise genexit
            data = (yield)
            self.data_window.append(data)
            next_filter.send(data)