add typing hints to make it easier for 3rd party developers to use the library (#90)

* add typing hints to make it easier for 3rd party developers to use the library

* remove unused devicetype enum to support python3.3

* add python 3.3 to travis and tox, install typing module in setup.py

pyHS100/protocol.py

@@ -2,6 +2,7 @@ import json
 import socket
 import struct
 import logging
+from typing import Any, Dict, Union
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -24,7 +25,9 @@ class TPLinkSmartHomeProtocol:
     DEFAULT_TIMEOUT = 5
 
     @staticmethod
-    def query(host, request, port=DEFAULT_PORT):
+    def query(host: str,
+              request: Union[str, Dict],
+              port: int = DEFAULT_PORT) -> Any:
         """
         Request information from a TP-Link SmartHome Device and return the
         response.
@@ -76,7 +79,7 @@ class TPLinkSmartHomeProtocol:
         return json.loads(response)
 
     @staticmethod
-    def encrypt(request):
+    def encrypt(request: str) -> bytearray:
         """
         Encrypt a request for a TP-Link Smart Home Device.
 
@@ -94,7 +97,7 @@ class TPLinkSmartHomeProtocol:
         return buffer
 
     @staticmethod
-    def decrypt(ciphertext):
+    def decrypt(ciphertext: bytes) -> str:
         """
         Decrypt a response of a TP-Link Smart Home Device.
 
@@ -104,9 +107,9 @@ class TPLinkSmartHomeProtocol:
         key = TPLinkSmartHomeProtocol.INITIALIZATION_VECTOR
         buffer = []
 
-        ciphertext = ciphertext.decode('latin-1')
+        ciphertext_str = ciphertext.decode('latin-1')
 
-        for char in ciphertext:
+        for char in ciphertext_str:
             plain = key ^ ord(char)
             key = ord(char)
             buffer.append(chr(plain))