NameError: name 'train_predict' is not defined #275

from sklearn.neighbors import KNeighborsClassifier
X_train_cv, X_test_cv, y_train_cv, y_test_cv = train_test_split(X_train, y_train, test_size = 0.3, random_state=100)
neighbors = []
accuracy = []
for n in range(3,10):
knn = KNeighborsClassifier(n_neighbors=n)
print("Number of neighbors is: {}".format(n))
train_predict(knn, X_train_cv, y_train_cv, X_test_cv, y_test_cv)
clf_ = knn.fit(X_train, y_train)
y_pred = clf_.predict(X_test)
neighbors.append(n)
accuracy.append( str(("%.2f" %(accuracy_score(y_test,y_pred)* 100) )))
accuracy.sort()
neighbors.sort()
plt.bar( list(range(3, 10)), accuracy, tick_label=neighbors, width=0.8, color="rgbymc")
plt.title("Optimizing Neighbours for KNN")
plt.xlabel("Neighbours")
plt.ylabel("accuracy")
plt.ylim(0)
plt.show()

ERROR
NameError Traceback (most recent call last)
in
6 knn = KNeighborsClassifier(n_neighbors=n)
7 print("Number of neighbors is: {}".format(n))
----> 8 train_predict(knn, X_train_cv, y_train_cv, X_test_cv, y_test_cv)
9 clf_ = knn.fit(X_train, y_train)
10 y_pred = clf_.predict(X_test)

NameError: name 'train_predict' is not defined