diff --git a/.codesandbox/Dockerfile b/.codesandbox/Dockerfile
new file mode 100644
index 0000000..9e15170
--- /dev/null
+++ b/.codesandbox/Dockerfile
@@ -0,0 +1 @@
+FROM python:3.11.3
diff --git a/.codesandbox/tasks.json b/.codesandbox/tasks.json
new file mode 100644
index 0000000..bfd023c
--- /dev/null
+++ b/.codesandbox/tasks.json
@@ -0,0 +1,13 @@
+{
+  // These tasks will run in order when initializing your CodeSandbox project.
+  "setupTasks": ["pip install -r requirements.txt"],
+
+  // These tasks can be run from CodeSandbox. Running one will open a log in the app.
+  "tasks": {
+    "start": {
+      "name": "start",
+      "command": "python main.py",
+      "runAtStart": true
+    }
+  }
+}
diff --git a/ex10.3.py b/ex10.3.py
index 072920b..463f634 100644
--- a/ex10.3.py
+++ b/ex10.3.py
@@ -1,8 +1,8 @@
-import string
 
-# fnand = input('Enter file: ')
+
+fnand = input('Enter file:')
 try:
-    lines = open('mbox-short.txt')
+    lines = open(fnand)
 except:
     print('File cannot be opened')
     exit()
@@ -10,13 +10,13 @@
 counts = dict()
 
 for line in lines:
-    # line = line.rsplit()
     line = line.split()
+    # line = line.rstrip()
+    # line = line.translate(line.maketrans(' ', ' ', string.punctuation))
+    # line = line.lower()
     for word in line:
-        word = word.split()
-        word =word.translate(word.maketrans('', '', string.punctuation))
+        word = line.split()
         for ch in word:
-            ch = ch.lower()
             if ch not in counts:
                 counts[ch] = 1
             else:
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..e69de29
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..e69de29