Added deprecation warning to bus.py and fixed notes

tmcl/bus.py

@@ -1,6 +1,45 @@
 import struct
 from .motor import Motor
 from .reply import Reply, TrinamicException
+import functools
+import inspect
+import warnings
+
+# NOTE(kgriffs): We don't want our deprecations to be ignored by default,
+# so create our own type.
+class DeprecatedWarning(UserWarning):
+    pass
+
+def deprecated(instructions):
+    """Flags a method as deprecated.
+    Args:
+        instructions: A human-friendly string of instructions, such
+            as: 'Please migrate to add_proxy() ASAP.'
+    By: Kurt Griffiths (kgriffs), https://gist.github.com/kgriffs/8202106
+    """
+    def decorator(func):
+        '''This is a decorator which can be used to mark functions
+        as deprecated. It will result in a warning being emitted
+        when the function is used.'''
+        @functools.wraps(func)
+        def wrapper(*args, **kwargs):
+            message = 'Call to deprecated function {}. {}'.format(
+                func.__name__,
+                instructions)
+
+            frame = inspect.currentframe().f_back
+
+            warnings.warn_explicit(message,
+                                    category=DeprecatedWarning,
+                                    filename=inspect.getfile(frame.f_code),
+                                    lineno=frame.f_lineno)
+
+            return func(*args, **kwargs)
+
+        return wrapper
+
+    return decorator
+
 
 
 # MSG_STRUCTURE = ">BBBBIB"
@@ -17,8 +56,9 @@
 REPLY_LENGTH_IIC = 8
 
 
-class Bus (object):
 
+class Bus (object):
+
     def __init__( self, serial, CAN = False ):
         self.CAN = CAN
         self.serial = serial
@@ -53,6 +93,17 @@ def _handle_reply (self, reply):
             raise TrinamicException(reply)
         return reply
 
+    @deprecated("Please use `get_module` in the future.")
+    def get_motor (self, address):
+        """
+        Deprecated!
+        Although the name suggests otherwise, this function retuns a handle
+        for a driver module (rather than a motor).
+        Use `get_module` instead, which also allows to select the default motor
+        driver on the module.
+        """
+        return Motor(self, address)
+
     def get_module (self, module_address = 1, motor = 0):
         """
             Returns object addressing motor number 'motor' on module 'module_address'.