Target Cell-limited Model - Python

import matplotlib.pyplot as plt  
import numpy as np  
%matplotlib inline

##Initial Conditions
t=[0]
T=[4*10**8]
I=[0.0001]
V=[3.5*10**(-1)]

##Parameters
beta=3.4*10**(-4.54)
delta=3.4
p=7.9*10**(-3)
c=3.3

n = 700
deltat = 0.01

for i in range(1,n+1):
    ti= t[-1] + deltat
    Ti= T[-1] - beta*T[-1]*V[-1]*deltat
    Ii= I[-1] + (beta*T[-1]*V[-1]-delta*I[-1])*deltat
    Vi= V[-1] + (p*I[-1]-c*V[-1])*deltat
    t.append(ti)
    T.append(Ti)
    I.append(Ii)
    V.append(Vi)


plt.plot(t,T, label='T',color='blue')
plt.plot(t,I, label='I',color='g')
plt.plot(t,V, label='V',color='r')
plt.xlabel("t")
plt.ylabel("y")
plt.ylim([10**(-5),10**(9)])
plt.yscale('log')
plt.legend()
plt.grid()
plt.show()