MSE

predicho=[20,22,23,24]
real=[21,24,20,31]

total=0
for i in range(4):
    total+=(predicho[i]-real[i])**2
mse=total/4

print(mse)

import numpy as np
pred=np.array(predicho)
obs=np.array(real)

cuadraticos=(pred-real)**2
print(cuadraticos)
mse=np.mean(cuadraticos)
print(mse)

from sklearn.metrics import mean_squared_error
mse=mean_squared_error(real,pred)
print(mse)