diff --git a/1/trebuchet.py b/1/trebuchet.py
index 1012870..5ee62df 100644
--- a/1/trebuchet.py
+++ b/1/trebuchet.py
@@ -2,27 +2,34 @@ from aocd.models import Puzzle
 from aocd import submit
 
 
-def calibrate(data: list) -> int:
+def calibrate(line: list) -> int:
     """
     Solve part a.
+    - Filter all digits from the line
+    - Add the first and the last and return result
     """
     # filter digits
-    digits = [c for c in data if c.isdigit()]
+    digits = [c for c in line if c.isdigit()]
     # return the sum of the first and the last digit
     return int(digits[0] + digits[-1])
 
 
-def translate(s: str) -> str:
+def translate(line: str) -> str:
     """
     Solve part b.
+    - Look for spelled out numbers
+    - replace them by a string where the first and last digit is preserved
+        - due to the fact that numbers can be part of each other
+    - return the translation and use the calibratoin function of part a.
     """
-    nums = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]
-    conv = ["o1e", "t2o", "t3e", "f4r", "f5e", "s6x", "s7n", "e8t", "n9e"]
 
-    for n, c in zip(nums, conv):
-        while n in s:
-            s = s.replace(n, c)
-    return s
+    numbers = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]
+    translation = ["o1e", "t2o", "t3e", "f4r", "f5e", "s6x", "s7n", "e8t", "n9e"]
+
+    for n, t in zip(numbers, translation):
+        while n in line:
+            line = line.replace(n, t)
+    return line
 
 
 if __name__ == "__main__":