Upd of print func to py3 syntax

Author: matheusfelipeog

docs/scenarios/speed.rst

@@ -176,17 +176,17 @@ What's the difference in speed? Let's try it!
 #primes implemented with Python
 import primes
 
-print "Cython:"
+print("Cython:")
 t1= time.time()
-print primesCy.primes(500)
+print(primesCy.primes(500))
 t2= time.time()
-print "Cython time: %s" %(t2-t1)
-print ""
-print "Python"
+print("Cython time: %s" %(t2-t1))
+print("")
+print("Python")
 t1= time.time()
-print primes.primes(500)
+print(primes.primes(500))
 t2= time.time()
-print "Python time: %s" %(t2-t1)
+print("Python time: %s" %(t2-t1))
 
 
 These lines both need a remark: