Below is a sample script to plot vector field using the package matplotlib in Python

```
import numpy as np
import matplotlib.pyplot as plt
x,y = np.meshgrid(np.linspace(-5,5,10),np.linspace(-5,5,10))
u = 1
v = 0
# (u,v) = (1,0) : left to right
# (u,v) = (0,1) : up
plt.quiver(x,y,u,v,color='blue')
plt.show()
```