diff --git a/exercises/capitalize/solution.py b/exercises/capitalize/solution.py
index e1c7ae3..eb6fbb2 100644
--- a/exercises/capitalize/solution.py
+++ b/exercises/capitalize/solution.py
@@ -8,12 +8,9 @@ def solve(s):
 
 
 if __name__ == '__main__':
-    fptr = open(os.environ['OUTPUT_PATH'], 'w')
+    with open(os.environ['OUTPUT_PATH'], 'w') as fptr:
+        s = input()
 
-    s = input()
+        result = solve(s)
 
-    result = solve(s)
-
-    fptr.write(result + '\n')
-
-    fptr.close()
+        fptr.write(result + '\n')
diff --git a/exercises/count_substring/solution.py b/exercises/count_substring/solution.py
index a53322c..f35f4e7 100644
--- a/exercises/count_substring/solution.py
+++ b/exercises/count_substring/solution.py
@@ -2,11 +2,7 @@
 # coding=utf-8
 
 def count_substring(string, sub_string):
-    count = 0
-    for i in range(len(string)):
-        if string[i:].startswith(sub_string):
-            count += 1
-    return count
+    return sum(bool(string[i:].startswith(sub_string)) for i in range(len(string)))
 
 if __name__ == '__main__':
     string = input().strip()
diff --git a/exercises/lists/find_the_runner_up_score/solution.py b/exercises/lists/find_the_runner_up_score/solution.py
index 7e3d005..4fe7085 100644
--- a/exercises/lists/find_the_runner_up_score/solution.py
+++ b/exercises/lists/find_the_runner_up_score/solution.py
@@ -5,9 +5,5 @@
     n = int(input())
     arr = map(int, input().split())
 
-    # remove duplicates
-    arr = list(dict.fromkeys(arr))
-    # sort
-    arr.sort()
-
+    arr = sorted(dict.fromkeys(arr))
     print(arr[-2])
diff --git a/exercises/lists/nested_lists/solution.py b/exercises/lists/nested_lists/solution.py
index a71c1cd..dcff0e4 100644
--- a/exercises/lists/nested_lists/solution.py
+++ b/exercises/lists/nested_lists/solution.py
@@ -1,13 +1,9 @@
 #!/usr/bin/env python
 # coding=utf-8
 
-scores_stats = []
-
-for _ in range(0,int(input())):
-    scores_stats.append([input(), float(input())])
-
+scores_stats = [[input(), float(input())] for _ in range(int(input()))]
 # Make a unique list of score, sort it and get the lowest second score
-second_lowest = sorted(list(set([score for name, score in scores_stats])))[1]
+second_lowest = sorted(list({score for name, score in scores_stats}))[1]
 
 # Iterate over the list of scores and names and print every match to the
 # lowest score we got above
diff --git a/solutions/loops/refactor_1.py b/solutions/loops/refactor_1.py
index 1e30b5b..3a3576f 100644
--- a/solutions/loops/refactor_1.py
+++ b/solutions/loops/refactor_1.py
@@ -10,10 +10,7 @@ def before_refactor():
 
     mushrooms = [Mushroom('Portabello', False), Mushroom('Oyster', False),
                  Mushroom('Death Cap', True)]
-    i = 0
-
-    for mushroom in mushrooms:
-        i += 1
+    for i, mushroom in enumerate(mushrooms, start=1):
         name = mushroom.name
         print('%d:"%s"' % (i, name))