Doing nothing with pass and Ellipsis

Python/pass-and-ellipsis.md

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+# Doing nothing with `pass` and `Ellipsis`
+
+In python, you can do nothing by typing `pass` - people also use `...` (`Ellipsis`), but this is also used in other places.
+
+For ignoring exceptions:
+
+```python
+try:
+    f(x)
+except ValueError:
+    pass
+```
+
+For writing skeleton code (to me, `pass` looks like it's intended to be empty, `...` looks like it will be filled in later).
+
+```python
+def my_fcn():
+    ...
+```
+
+You can put anything in place of the `...` here though, so people often just write a docstring:
+
+```python
+def my_fcn():
+   """
+   Do some things and stuff
+   """
+```
+
+Via: [Richard](https://github.com/richard-lane)
+
+## Postscript
+
+For skeleton code you could also do:
+
+```python
+def my_fcn():
+    raise NotImplementedError
+```
+
+or:
+
+```python
+def my_fcn():
+    return NotImplemented
+```
+
+(these do different things)