All,
Following BrenBarn's comment, I've tried to restart the Code Editor in Canopy and it seems to work now:
Welcome to EPD's interactive data-analysis environment!
with pylab-backend: wx
Type '?' for more information.
Welcome to pylab, a matplotlib-based Python environment [backend: WXAgg].
For more information, type 'help(pylab)'.
%run D:/Python/use_sine_test.py
u
Out[2]: 0.8414709848078965
Thanks for your comments!