[doc][algorithms] Fix print statements

doc/algorithms.rst

@@ -301,16 +301,16 @@ or by iterating over the list:
 
     # 'inputs' is the list of inputs of the processing block
 
-    print inputs['labels'].data_format
+    print(inputs['labels'].data_format)
 
     for index in range(0, inputs.length):
-        print inputs[index].data_format
+        print(inputs[index].data_format)
 
     for input in inputs:
-        print input.data_format
+        print(input.data_format)
 
     for input in inputs[0:2]:
-        print input.data_format
+        print(input.data_format)
 
 Additionally, the following method is useable on a **list of inputs**: