Explain if the runtime of the function below is O(len(L)).

def checkWalk(A,L):

n = len(A)

for i in range(0,len(L)-1):

if(L[i]>=1 and L[i]<=n):

if(A[L[i]-1][L[i+1]-1]==0 and A[L[i+1]-1][L[i]-1]==0):

return False

else:

print("Vertex %d is not in the Graph."%(L[i]));

return True