finding the closest feature given a set of Genomic coordinates

I have a bed file which contains peak information for a ChIP-seq data. I want to find the genes that are closest to these peaks.

I am aware that many softwares can do this job. cistrome-Galaxy pipeline http://cistrome.org/ap/ from shirley liu's lab in Harvard,  bioconductor package ChIPpeakAnno http://www.bioconductor.org/packages/2.12/bioc/html/ChIPpeakAnno.html

are tools can deal with this kind of task. In addition to them, bedtool is a very good tool for Genomic Interval manipulation.  See a post here http://www.biostars.org/p/53561/

However, I want to go a little bit further to learn the Interval Tree data structure to deal with this kind of problem as mentioned in my last post and the post from Biostar.

I will have a look at the bx-python package.
http://www.biostars.org/p/99/