---
+# Using the tools
+
+Before doing anything, create a new branch in Git
+
+* This will keep your changes isolated
+
+Experiment in IPython (ephemeral, for us)
+
+Once you've got something working, copy the code into a `.py` file (permanent and reusable)
+
+```python
+from imp import reload
+
+import test
+reload(test)
+from test import *
+```
+
+Re-evaluate the second cell to reload the file into the IPython notebook
+
+When you've made progress, make a Git commit
+
+* Commit early and often!
+
+When you've finished, change back to `master` branch and `merge` the development branch
+
+---
+
# The [string module](http://docs.python.org/3.3/library/string.html) is your friend
```python
```
---
+
# DRY and YAGNI
Is your code DRY?
---
-# Doing all the letters
+# Doing the whole message
## Test-first developement
---
-# Doing all the letters
+# Doing the whole message
## Abysmal
ciphertext += caesar_encipher_letter(plaintext[i], key)
```
+Try it in IPython
+
---
-# Doing all the letters
+# Doing the whole message
## Bad
---
-# Doing all the letters
+# Doing the whole message
## Good (but unPythonic)
---
-# Doing all the letters
+# Doing the whole message
## Best