im trying to draw closed contour around axis graph using x y coordinates, and my graph looks bad like a long line.
what im missing?

import matplotlib.pyplot as plt
x = ['-18.6337', '-17.6337', '-16.6337', '-15.6337', '-14.6337', '-13.6337', '-12.6337', '-11.6337', '-10.6337', '-9.63366', '-8.63366', '-7.63366', '-6.63366', '-5.63366', '-4.63366', '-3.63366', '-2.63366', '-1.63366', '-0.633663', '0.366337', '1.36634', '2.36634', '3.36634', '4.36634', '5.36634', '6.36634', '7.36634', '8.36634', '9.36634', '10.3663', '11.3663', '12.3663', '13.3663', '14.3663', '15.3663', '16.3663', '17.3663', '18.3663', '19.3663', '20.1663', '20.7663', '21.1663', '21.3663', '21.3663', '21.3663', '21.3663', '21.1663', '20.9663', '20.5663', '19.9663', '19.1663', '18.3663', '17.3663', '16.3663', '15.3663', '14.3663', '13.3663', '12.3663', '11.3663', '10.3663', '9.36634', '8.36634', '7.36634', '6.36634', '5.36634', '4.36634', '3.36634', '2.36634', '1.36634', '0.366337', '-0.633663', '-1.63366', '-2.63366', '-3.63366', '-4.63366', '-5.63366', '-6.63366', '-7.63366', '-8.63366', '-9.63366', '-10.6337', '-11.6337', '-12.6337', '-13.6337', '-14.6337', '-15.6337', '-16.6337', '-17.6337', '-18.6337', '-19.4337', '-20.2337', '-20.8337', '-21.2337', '-21.4337', '-21.6337', '-21.6337', '-21.6337', '-21.4337', '-21.0337', '-20.4337', '-19.6337']
y = ['-5.79802', '-6.39802', '-6.79802', '-7.19802', '-7.59802', '-7.79802', '-7.99802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-8.19802', '-7.99802', '-7.79802', '-7.39802', '-6.99802', '-6.39802', '-5.99802', '-5.39802', '-4.79802', '-3.99802', '-3.19802', '-2.19802', '-1.19802', '-0.198021', '0.801979', '1.80198', '2.80198', '3.80198', '4.60198', '5.40198', '6.00198', '6.60198', '7.00198', '7.40198', '7.60198', '8.00198', '8.20198', '8.40198', '8.60198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.80198', '8.60198', '8.40198', '8.20198', '8.00198', '7.80198', '7.60198', '7.40198', '7.00198', '6.40198', '5.60198', '4.80198', '3.80198', '2.80198', '1.80198', '0.801979', '-0.198021', '-1.19802', '-2.19802', '-3.19802', '-4.19802', '-4.99802']

plt.plot(x,y)
plt.show()