See their github page for install details.
I installed on my local machine as a first test; I created a virtual environment for Python2.7.14, then installed using their pip instructions. Because I am using Homebrew as a package manager, my python binaries are in a different place from a default install.
cd $HOME
virtualenv py27.14 -p /usr/local/Cellar/python/2.7.14/bin/python2.7
source py27.14/bin/activate
pip install pybold
There's an error in their example online - you have to change taxons to taxon. See the commented line:
import pybold.specimen
taxons_list = ['Achaeorhizomycetes', 'Arthoniomycetes']
sc = pybold.specimen.SpecimensClient()
## here's their error - note their example uses "...sc.get(taxons = ..." but you want just "...sc.get(taxon = ..."
specimen_list = sc.get(taxon='|'.join(taxons_list))
for specimen in specimen_list:
print specimen.process_id