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Notes/01_Introduction/01_Python.md

@@ -183,4 +183,4 @@ exercise work. For example:
 >>>
 ```
 
-[Next]("02_Hello_World.html")
+[Next]("02_Hello_world")

Notes/01_Introduction/02_Hello_world.md

@@ -503,4 +503,4 @@ an identifying filename and line number.
 * Fix the error
 * Run the program successfully
 
-[Next]("03_Numbers.html")
+[Next]("03_Numbers")

Notes/01_Introduction/03_Numbers.md

@@ -232,4 +232,4 @@ Months 309
 
 While you’re at it, fix the program to correct the for overpayment that occurs in the last month.
 
-[Next]("04_Strings.html")
+[Next]("04_Strings")

Notes/01_Introduction/04_Strings.md

@@ -420,4 +420,4 @@ For example, a popular alternative to Python's normal interactive mode
 is IPython (http://ipython.org).  IPython provides some nice features
 such as tab-completion of method names, more integrated help and more.
 
-[Next]("05_Lists.html")
+[Next]("05_Lists")

Notes/01_Introduction/05_Lists.md

@@ -402,4 +402,4 @@ example, a list that consists entirely of numbers or a list of text
 strings.  Mixing different kinds of data together in the same list is
 often a good way to make your head explode so it's best avoided.
 
-[Next]("06_Files.html")
+[Next]("06_Files")

Notes/01_Introduction/06_Files.md

@@ -214,4 +214,4 @@ Try it:
 >>>
 ```
 
-[Next]("07_Functions.html")
+[Next]("07_Functions")