Fixed doctest for Collector
Fixed doctest for Collector

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