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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 enable_tracing(self, thread_trace_func=None):
        '''
        Enables tracing.

        If in regular mode (tracing), will set the tracing function to the tracing
        function for this thread -- by default it's `PyDB.trace_dispatch`, but after
        `PyDB.enable_tracing` is called with a `thread_trace_func`, the given function will
        be the default for the given thread.
        '''
        if self.frame_eval_func is not None:
            self.frame_eval_func()
            pydevd_tracing.SetTrace(self.dummy_trace_dispatch)
            return

        if thread_trace_func is None:
            thread_trace_func = self.get_thread_local_trace_func()
        else:
            self._local_thread_trace_func.thread_trace_func = thread_trace_func

        pydevd_tracing.SetTrace(thread_trace_func)