generator done

generators/wiki.txt

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+-> What are generators?
+
+    Generators are used to generate range of values
+    without using extra space.
+
+    for example, range(1,100) creates number from 1 to
+    100 but in this the procedure is as follows:
+
+    -> initialize with value 1.
+    -> returns the value.
+    -> increment it by one.
+    -> Repeat this same process from step 2,
+        until all values are generated with
+        the given range.
+
+
+    * generators is a iterator but iterator
+     is not necessarily a generator.
+
+-> How to create your own generators?
+
+    for ex:
+
+        def generator_function(num):
+            for i in range(num):
+                yield i
+
+        g = generator_function(10)
+        next(g)
+        next(g)
+        print(next(g))
+
+    Two keywords are used here:
+    -> yield: This is used to make functions a
+                generator.
+
+    -> next: This is used to get the next value from
+            generator function
+
+    Note that unlike creating a list and then returning
+    the range of values, generators don't take extra 
+    space to have range of values.