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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 start(self, name: str, increment_count: bool = True) -> None: """ Start a named timer. Args: name: name of the timer increment_count: increment the start count for this timer """

        if not self._timing:
            return
        now = get_now_utc_pendulum()

        # If we were already timing something else, pause that.
        if self._stack:
            last = self._stack[-1]
            self._totaldurations[last] += now - self._starttimes[last]

        # Start timing our new thing
        if name not in self._starttimes:
            self._totaldurations[name] = datetime.timedelta()
            self._count[name] = 0
        self._starttimes[name] = now
        if increment_count:
            self._count[name] += 1
        self._stack.append(name)