import pandas
import matplotlib.pyplot as plt
iris=pandas.read_csv("iris.csv")
x=iris.loc[:,"petal_length"].tolist()
y=iris.loc[:,"petal_width"].tolist()
specie=lab=iris.loc[:,"species"].tolist()
N=len(specie)

plt.axis('equal')
plt.scatter([x[k] for k in range(N) if specie[k]==0], [y[k] for k in range(N) if specie[k]==0], marker='o', color='g', label='setosa')
plt.scatter([x[k] for k in range(N) if specie[k]==1], [y[k] for k in range(N) if specie[k]==1], marker='v',  color='r', label='versicolor')
plt.scatter([x[k] for k in range(N) if specie[k]==2], [y[k] for k in range(N) if specie[k]==2], marker='x',  color='b', label='virginica')
plt.legend()
plt.show()