As you can see in this example, you should define X and Y in two separated arrays, so you can do it like this :
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(2)
y = [0.75565,0.77615]
fig, ax = plt.subplots()
plt.bar(x, y)
# set your labels for the x axis here :
plt.xticks(x, ('test1', 'test2'))
plt.show()
the final plot would be like :

UPDATE
If you want to draw each bar with a different color, you should call the bar method multiple times and give it colors to draw, although it has default colors :
import matplotlib.pyplot as plt
import numpy as np
number_of_points = 2
x = np.arange(number_of_points)
y = [0.75565,0.77615]
fig, ax = plt.subplots()
for i in range(number_of_points):
plt.bar(x[i], y[i])
# set your labels for the x axis here :
plt.xticks(x, ('test1', 'test2'))
plt.show()

or you can do it even more better and choose the colors yourself :
import matplotlib.pyplot as plt
import numpy as np
number_of_points = 2
x = np.arange(number_of_points)
y = [0.75565,0.77615]
# choosing the colors and keeping them in a list
colors = ['g','b']
fig, ax = plt.subplots()
for i in range(number_of_points):
plt.bar(x[i], y[i],color = colors[i])
# set your labels for the x axis here :
plt.xticks(x, ('test1', 'test2'))
plt.show()
