Fixed duplicated imports in ipython extension
Fixed duplicated imports in ipython extension

ioam/holoviews,vascotenner/holoviews,vascotenner/holoviews,basnijholt/holoviews,basnijholt/holoviews,vascotenner/holoviews,ioam/holoviews,basnijholt/holoviews,ioam/holoviews