Ibm bluemix timeout after 60sec

I try to run a loop for 1000 times, when the program reaches 60 seconds typing this error

Internal Server Error

Sample code

for i in range(1000,0,-1):
    wc = fun_A(funInput) #function
    time.sleep(i/1000)

Εrror is only when reach the 60sec. I try for a repetition number of less than 60sec and runs normally