You can use the xticks
command to do so. See the following snippet -
>>> listHours = ['00:00:000-10:00:000', '10:00:000-20:00:000', '20:00:000-30:00:000','30:00:000-40:00:000', '40:00:000-50:00:000', '50:00:000-00:00:000']
>>> listNumbers = ['0.01', '0.02', '0.03', '0.05', '0.05', '0.03']
>>> listNumbers = [float(elem) for elem in listNumbers] # Convert to a list of floats.
>>> plt.plot(listNumbers)
>>> plt.xticks(range(len(listHours)), listHours, size='small')
>>> plt.show()
It gives you a figure like this