Matplotlib horizontal barh graph not displaying correctly within ranges. How to make a gnat style chart

Question

I'm not sure what I'm supposed to do to make this kind of thing work. I need something that will display my bar graphs like a gant chat. Each bar should show right after the next one. Notice how it only works for the first one. What can I do to make it work like I would expect. Where each bar is drawn at the correct time and ends at the correct time.

plt.rcdefaults()
fig, ax = plt.subplots()
people = [0,1,2,3,4]
peopleStr = [str(i) for i in people]
y_pos = np.arange(len(people))
target_bars_start = [0.00, 10.0, 30.0, 40.0, 50.0]
target_bars_end =   [10.0, 30.0, 40.0, 50.0, 70.0]
target_bars_start2 = [5.00, 13.0, 32.0, 40.0, 45.0]
target_bars_end2 =   [13.0, 32.0, 40.0, 45.0, 60.0]
plt.barh(y_pos, left=target_bars_start, width=target_bars_end,height=0.10,color="green", label="Time 1")
#plt.barh(y_pos+0.2, left=target_bars_start2, width=target_bars_end2,height=0.10,color="red", label="Time 2")
ax.set_yticks(y_pos, labels=peopleStr)
ax.invert_yaxis() 
ax.set_ylabel('Person')
ax.set_xlabel('Completion time')
fig.tight_layout()
plt.legend()
plt.show()

What I expect is that bar is drawn right after the other one.Again for sime reason it only works on the first 2. 0 and 1. The rest do not display correctly. Notice the second one is not even stopping at 30 but bleeds into like 41.