IPython error message is fixed
bikeshedding (style fixes):

- PEP8 spaces for inline comments;
- more meaningful variable names instead of `a,b=Pipe()` (taken from Python docs);
- don't shadow builtins 'dict' and 'dir' with local variables;
- remove unneeded indentation;
- use 'with' for opening files
Merge pull request #37 from kmike/small-fixes

Small fixes