merge Aj argparse branch into master

argparse material for "Parsing Command Line Arguments" section of the course

_episodes/04-argparse.md

@@ -87,7 +87,6 @@ keypoints:
 > to find another function that could get this for you.
 {: .challenge}
 
-{% include links.md %}
 
 > ##argparse
 
@@ -209,8 +208,8 @@ keypoints:
 > import argparse
 > if __name__ == "__main__":
 > 	parser = argparse.ArgumentParser()
-> 	parser.add_argument("--number1", help=" first number")
-> 	parser.add_argument("--number2", help=" second number")
+> 	parser.add_argument("--number1", type=int, help=" first number")
+> 	parser.add_argument("--number2", type=int, help=" second number")
 > 	parser.add_argument("--operation", help=" operation")
 > 	args = parser.parse_args()
 >
@@ -251,8 +250,8 @@ keypoints:
 > import argparse
 > if __name__ == "__main__":
 > 	parser = argparse.ArgumentParser()
-> 	parser.add_argument("-n1", "--number1", help=" first number")
-> 	parser.add_argument("-n2", "--number2", help=" second number")
+> 	parser.add_argument("-n1", "--number1", type=int, help=" first number")
+> 	parser.add_argument("-n2", "--number2", type=int, help=" second number")
 > 	parser.add_argument("-op", "--operation", help=" operation", \
 > 						choices=['add','substract','multiply'])
 > 	args = parser.parse_args()
@@ -275,8 +274,8 @@ keypoints:
 > import argparse
 > if __name__ == "__main__":
 > 	parser = argparse.ArgumentParser()
-> 	parser.add_argument("-n1", "--number1", help=" first number")
-> 	parser.add_argument("-n2", "--number2", help=" second number")
+> 	parser.add_argument("-n1", "--number1", type=int, help=" first number")
+> 	parser.add_argument("-n2", "--number2", type=int, help=" second number")
 > 	parser.add_argument("-op", "--operation", help=" operation", \
 > 						choices=['add','substract','multiply'])
 > 	parser.add_argument("-d", "--debug", help=" print out the given argument", action="store_true")
@@ -302,8 +301,8 @@ keypoints:
 > import argparse
 > if __name__ == "__main__":
 > 	parser = argparse.ArgumentParser()
-> 	parser.add_argument("-n1", "--number1", help=" first number")
-> 	parser.add_argument("-n2", "--number2", help=" second number")
+> 	parser.add_argument("-n1", "--number1", type=int, help=" first number")
+> 	parser.add_argument("-n2", "--number2", type=int, help=" second number")
 > 	parser.add_argument("-op", "--operation", help=" operation", \
 > 						choices=['add','substract','multiply'])
 > 	group = parser.add_mutually_exclusive_group()
@@ -334,7 +333,7 @@ keypoints:
 >> import argparse
 >> if __name__ == "__main__":
 >>   parser = argparse.ArgumentParser()
->> 	 parser.add_argument("-n", "--numbers", nargs='+', help=" first number")
+>> 	 parser.add_argument("-n", "--numbers", nargs='+', type=int, help=" first number")
 >> 	 parser.add_argument("-op", "--operation", help=" operation", choices=['add','substract','multiply'])
 >> 	 group = parser.add_mutually_exclusive_group()
 >> 	 group.add_argument("-v", "--verbose", action="store_true")
@@ -354,7 +353,7 @@ keypoints:
 {: .challenge}
 
 > ## Options & Arguments Revisited
-> In an earlier exercise (),
+> In an [earlier exercise](#options--arguments),
 > you filled in the blanks in code designed to
 > parse options and arguments from the command line using `sys.argv`.
 > Use what you've learned about `argparse` to write a parser to replace that
@@ -378,4 +377,6 @@ keypoints:
 > Do you think this is better than the approach we used before?
 > If so, do you consider the improvement sufficient to be worth the effort?
 >
-{: .challenge }
\ No newline at end of file
+{: .challenge }
+
+{% include links.md %}
\ No newline at end of file