diff --git a/02-cpu-commnads/hex2bin.py b/02-cpu-commnads/hex2bin.py
index 55c6faf..6ac4acf 100755
--- a/02-cpu-commnads/hex2bin.py
+++ b/02-cpu-commnads/hex2bin.py
@@ -1,11 +1,18 @@
 #!/usr/bin/python3
-import sys
+import argparse
 
 def hex2bin(hexNum: str) -> None:
     return bin(int(hexNum, 16))
 
-if (len(sys.argv) > 1):
-    print(hex2bin(sys.argv[1]))
-else:
-    print("No number passed")
+parser = argparse.ArgumentParser(description="convert hex number to bin right in terminal")
+parser.add_argument('-s', '--stdin', action='store_true', help="if passed takes input from terminal arguments")
+parser.add_argument('number', nargs='?')
+
+args = parser.parse_args()
+if args.stdin:
+    print(hex2bin(input()))
+elif args.number:
+    print(hex2bin(args.number))
+else:
+    print("something went wrong")