solved the first 5 problems

03.py

@@ -0,0 +1,19 @@
+import helper, cryptlib
+
+def main():
+    hexstring = helper.read_file("data/03.txt")
+    candidates = []
+    for key in range(256):
+        decrypt = cryptlib.single_byte_xor(hexstring, key)
+        english_score = cryptlib.score_english_lang(decrypt) 
+        result = {
+            'key': key,
+            'score': english_score,
+            'plaintext': decrypt
+        }
+        candidates.append(result)
+
+    print(sorted(candidates, key=lambda c: c['score'], reverse=True)[0])
+
+if __name__ == '__main__':
+    main()