diff --git a/challenge.py b/challenge.py
index 93a85f8..a9e07f8 100644
--- a/challenge.py
+++ b/challenge.py
@@ -71,15 +71,31 @@
     },
 ]
 
+def is_homeless(dev):
+    dev.update( { 'homeless': dev['organization'] == '' } )
+    return dev
+
+def is_old(dev):
+    dev.update( { 'old': dev['age'] > 30 } )
+    return dev
+
 
 def run():
+    # Using filter, generate a list with all the python devs
+    all_python_devs = filter(lambda dev: dev['language'] == 'python', DATA)
+
+    # Using filter, generate a list with all the Platzi workers
+    all_Platzi_workers = filter(lambda dev: dev['organization'] == 'Platzi', DATA)
 
-    all_python_devs =  # Using filter, generate a list with all the python devs
-    all_Platzi_workers =  # Using filter, generate a list with all the Platzi workers
-    adults =  # Using filter, generate a list with all people over 18 years old
-    workers =  # Using map, generate a new list of people with a key 'homeless' with True or False values, if 'organization' have something or not
-    old_people =  # Using map, generate a new list of people with a key 'old' with True or False values, if 'age' is greater than 30 or not
+    # Using filter, generate a list with all people over 18 years old
+    adults = filter(lambda dev: dev['age'] >= 18, DATA)
 
+    # Using map, generate a new list of people with a key 'homeless' with True or False values, if 'organization' have something or not
+    workers = map(is_homeless , DATA)
+    
+    # Using map, generate a new list of people with a key 'old' with True or False values, if 'age' is greater than 30 or not
+    old_people = map(is_old, DATA)
+    
     print('Python devs: ')
     for dev in all_python_devs:
         print(dev['name'])