error importing igraph

On importing igraph in python, I get an error (see below). Since igraph is not part of anaconda, I executed the below outlined steps for installation.

What is libglpk.35.dylib, how should I load it, and why is this problem occurring?

igraph cannot be imported

'' import igraph
'' Traceback (most recent call last):
''   File "<stdin>", line 1, in <module>
''   File "/Users/claushaslauer/anaconda/lib/python2.7/site-packages/igraph/__init__.py", line 34, in <module>
    '' from igraph._igraph import *
'' ImportError: dlopen(/Users/claushaslauer/anaconda/lib/python2.7/site-packages/igraph/_igraph.so, 2): Library not loaded: /usr/local/lib/libgmp.10.dylib
''   Referenced from: /usr/local/lib/libglpk.35.dylib
''   Reason: image not found

installation steps

install homebrew via ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
install pkg-config (via igraph-help) brew install pkg-config
install igraph via homebrew: brew install igraph
link: brew install homebrew/science/igraph
pip install python-igraph

following suggestions from Evert:

brew uninstall igraph
brew uninstall gmp
brew uninstall glkp -- Error: No such keg: /usr/local/Cellar/glkp
brew install igraph

==> Installing igraph from homebrew/homebrew-science ==> Installing igraph dependency: gmp ==> Downloading https://homebrew.bintray.com/bottles/gmp-6.0.0a.yosemite.bottle. Already downloaded: /Library/Caches/Homebrew/gmp-6.0.0a.yosemite.bottle.tar.gz ==> Pouring gmp-6.0.0a.yosemite.bottle.tar.gz Error: The brew link step did not complete successfully The formula built, but is not symlinked into /usr/local Could not symlink include/gmp.h Target /usr/local/include/gmp.h already exists. You may want to remove it: rm '/usr/local/include/gmp.h'

To force the link and overwrite all conflicting files: brew link --overwrite gmp

To list all files that would be deleted: brew link --overwrite --dry-run gmp

Possible conflicting files are: /usr/local/include/gmp.h /usr/local/lib/libgmp.a ==> Summary