Minor fixes

docs/advanced/transports.md

@@ -175,7 +175,7 @@ class HelloWorldTransport(httpx.BaseTransport):
         return httpx.Response(200, json={"text": "Hello, world!"})
 ```
 
-Or this example, which uses a custom transport and `httpx.Mounts` to always redirect `http://` requests.
+Or this example, which uses a custom transport and `mounts` parameter to always redirect `http://` requests.
 
 ```python
 class HTTPSRedirect(httpx.BaseTransport):
@@ -187,11 +187,11 @@ class HTTPSRedirect(httpx.BaseTransport):
         return httpx.Response(303, headers={"Location": str(url)})
 
 # A client where any `http` requests are always redirected to `https`
-transport = httpx.Mounts({
+mounts = {
     'http://': HTTPSRedirect()
     'https://': httpx.HTTPTransport()
-})
+}
-client = httpx.Client(transport=transport)
+client = httpx.Client(mounts=mounts)
 ```
 
 A useful pattern here is custom transport classes that wrap the default HTTP implementation. For example...