fix non-unique reference labels

Author: mmcky

lectures/mathfoo.py

@@ -0,0 +1 @@
+pi = 'foobar'

lectures/mod.py

@@ -0,0 +1 @@
+print(__name__)

lectures/names.md

@@ -9,7 +9,7 @@ kernelspec:
   name: python3
 ---
 
-(oop_intro)=
+(oop_names)=
 ```{raw} jupyter
 <div id="qe-notebook-header" align="right" style="text-align:right;">
         <a href="https://quantecon.org/" title="quantecon.org">
@@ -18,19 +18,8 @@ kernelspec:
 </div>
 ```
 
-<style>
-  .auto {
-    width: 100%;
-    height: auto;
-    } 
-</style>
-
 # OOP I: Names and Namespaces
 
-```{contents} Contents
-:depth: 2
-```
-
 ## Overview
 
 This lecture is all about variable names, how they can be used and how they are
@@ -42,7 +31,7 @@ handling names is elegant and interesting.
 In addition, you will save yourself many hours of debugging if you have a good
 understanding of how names work in Python.
 
-(name_res)=
+(var_names)=
 ## Variable Names in Python
 
 ```{index} single: Python; Variable Names

lectures/oop_intro.md

@@ -18,19 +18,8 @@ kernelspec:
 </div>
 ```
 
-<style>
-  .auto {
-    width: 100%;
-    height: auto;
-    } 
-</style>
-
 # OOP I: Names and Objects
 
-```{contents} Contents
-:depth: 2
-```
-
 ## Overview
 
 The traditional programming paradigm (think Fortran, C, MATLAB, etc.) is called [procedural](https://en.wikipedia.org/wiki/Procedural_programming).
@@ -714,8 +703,8 @@ Next `g` is called via `y = g(10)`, leading to the following sequence of actions
 ```
 
 
-(mutable_vs_immutable)=
-### {index}`Mutable <single: Mutable>` Versus {index}`Immutable <single: Immutable>` Parameters
+(mutable_vs_immutable2)=
+### {index}`Mutable <single: Mutable>` versus {index}`Immutable <single: Immutable>` parameters
 
 This is a good time to say a little more about mutable vs immutable objects.
 

lectures/test.py

@@ -0,0 +1,8 @@
+def g(x):
+    a = 1
+    x = x + a
+    return x
+
+a = 0
+y = g(10)
+print("a = ", a, "y = ", y)