Moves EncryptedBlob to common

common/blob.py

@@ -0,0 +1,9 @@
+import re
+
+
+class Blob:
+    def __init__(self, data):
+        if type(data) is not str or re.search(r"^[0-9A-Fa-f]+$", data) is None:
+            raise ValueError("Non-Hex character found in transaction.")
+
+        self.data = data