Add argument parser to new examples

Author: tiagocoutinho

README.rst

@@ -157,7 +157,17 @@ StreamWriter objects:
 
 
     async def main():
-        reader, writer = await asyncio.open_connection('localhost', 502)
+        # Parse command line arguments
+        parser = ArgumentParser()
+        parser.add_argument("-a", "--address", default="localhost:502")
+
+        args = parser.parse_args()
+        if ":" not in args.address:
+            args.address += ":502"
+        host, port = args.address.rsplit(":", 1)
+        port = int(port)
+
+        reader, writer = await asyncio.open_connection(host, port)
 
         # Returns a message or Application Data Unit (ADU) specific for doing
         # Modbus TCP/IP.

scripts/examples/simple_asyncio_tcp_client.py

@@ -1,18 +1,29 @@
 #!/usr/bin/env python
 # scripts/examples/simple_async_tcp_client.py
 import asyncio
+from argparse import ArgumentParser
 
 from umodbus import conf
 from umodbus.client import tcp
-from umodbus.client.asynch import send_message
+from umodbus.client.tcp.asynch import send_message
 
 
 # Enable values to be signed (default is False).
 conf.SIGNED_VALUES = True
 
 
 async def main():
-    reader, writer = await asyncio.open_connection('localhost', 502)
+    # Parse command line arguments
+    parser = ArgumentParser()
+    parser.add_argument("-a", "--address", default="localhost:502")
+
+    args = parser.parse_args()
+    if ":" not in args.address:
+        args.address += ":502"
+    host, port = args.address.rsplit(":", 1)
+    port = int(port)
+
+    reader, writer = await asyncio.open_connection(host, port)
 
     # Returns a message or Application Data Unit (ADU) specific for doing
     # Modbus TCP/IP.

scripts/examples/simple_curio_tcp_client.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 # scripts/examples/simple_curio_tcp_client.py
 import curio
+from argparse import ArgumentParser
 
 from umodbus import conf
 from umodbus.client import tcp
@@ -31,7 +32,17 @@ async def readexactly(self, n):
 
 
 async def main():
-    sock = await curio.open_connection('localhost', 502)
+    # Parse command line arguments
+    parser = ArgumentParser()
+    parser.add_argument("-a", "--address", default="localhost:502")
+
+    args = parser.parse_args()
+    if ":" not in args.address:
+        args.address += ":502"
+    host, port = args.address.rsplit(":", 1)
+    port = int(port)
+
+    sock = await curio.open_connection(host, port)
     stream = CurioStream(sock)
 
     # Returns a message or Application Data Unit (ADU) specific for doing