MAINT Make bayesian import depend on whether pymc3 is installed.
MAINT Make bayesian import depend on whether pymc3 is installed.

YihaoLu/pyfolio,chayapan/pyfolio,yanheven/pyfolio,ChinaQuants/pyfolio,raybuhr/pyfolio,sketchytechky/pyfolio,dursk/pyfolio,YihaoLu/pyfolio,sketchytechky/pyfolio,femtotrader/pyfolio,ChinaQuants/pyfolio,dursk/pyfolio,r0k3/pyfolio,femtotrader/pyfolio,r0k3/pyfolio,quantopian/pyfolio,raybuhr/pyfolio,quantopian/pyfolio,yanheven/pyfolio