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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 chrome_tracing_dump(self, filename=None):
 """Return a list of profiling events that can viewed as a timeline. To view this information as a timeline, simply dump it as a json file by passing in "filename" or using using json.dump, and then load go to chrome://tracing in the Chrome web browser and load the dumped file. Make sure to enable "Flow events" in the "View Options" menu. Args: filename: If a filename is provided, the timeline is dumped to that file. Returns: If filename is not provided, this returns a list of profiling events. Each profile event is a dictionary. """

        # TODO(rkn): Support including the task specification data in the
        # timeline.
        # TODO(rkn): This should support viewing just a window of time or a
        # limited number of events.

        profile_table = self.profile_table()
        all_events = []

        for component_id_hex, component_events in profile_table.items():
            # Only consider workers and drivers.
            component_type = component_events[0]["component_type"]
            if component_type not in ["worker", "driver"]:
                continue

            for event in component_events:
                new_event = {
                    # The category of the event.
                    "cat": event["event_type"],
                    # The string displayed on the event.
                    "name": event["event_type"],
                    # The identifier for the group of rows that the event
                    # appears in.
                    "pid": event["node_ip_address"],
                    # The identifier for the row that the event appears in.
                    "tid": event["component_type"] + ":" +
                    event["component_id"],
                    # The start time in microseconds.
                    "ts": self._seconds_to_microseconds(event["start_time"]),
                    # The duration in microseconds.
                    "dur": self._seconds_to_microseconds(event["end_time"] -
                                                         event["start_time"]),
                    # What is this?
                    "ph": "X",
                    # This is the name of the color to display the box in.
                    "cname": self._default_color_mapping[event["event_type"]],
                    # The extra user-defined data.
                    "args": event["extra_data"],
                }

                # Modify the json with the additional user-defined extra data.
                # This can be used to add fields or override existing fields.
                if "cname" in event["extra_data"]:
                    new_event["cname"] = event["extra_data"]["cname"]
                if "name" in event["extra_data"]:
                    new_event["name"] = event["extra_data"]["name"]

                all_events.append(new_event)

        if filename is not None:
            with open(filename, "w") as outfile:
                json.dump(all_events, outfile)
        else:
            return all_events