Plot signal data and skip frame with missing information using Matplotlib FuncAnimation

Question

I am imitating getting stream of data where not each "message" line has the information I want to plot in live mode. Since each line will still be read, how can I skip one iteration (frame) and therefore skip plot update for 1 frame until next iteration that returns data comes along. My code has the following structure:

fig, ax = plt.subplots()
line, = ax.plot([], [])

lap_stat = []
file = open(path + 'file.log', 'r')

def update(lap_stat):

    #Plot lap number on x-axis, lap time on y-axis from lap_stat list that 
    #contains a tuple

    line.set_data(lap_stat[0], lap_stat[1])
    return line,
    
def data_gen():

    while True:
        line = file.readline()

        #Get data from line
        #Apply conditions, if line doesn't contain relevant information nothing happens
        #If data is present in line, save data as tuple [lap, lap_time] to lap_stat

        yield lap_stat

ani = FuncAnimation(fig, update, data_gen, interval=100, blit=True)
plt.show() 

Not each line has the relevant information, so if at current frame no information was appended the input list at update(lap_stat) function is empty, nothing gets plotted and the process dies. How can I modify my code to only plot information when it is returned? Plotting 0's also not an option, if I plot lap times from lap 0-10 and the then next data point is lap 15, I want the point from lap 10 to be connected to point 15. Hope it makes, thank you!