how to use sklearn when target variable is a proportion

There are standard ways of predicting proportions such as logistic regression (without thresholding) and beta regression. There have already been discussions about this:

http://scikit-learn-general.narkive.com/4dSCktaM/using-logistic-regression-on-a-continuous-target-variable

http://scikit-learn-general.narkive.com/lLVQGzyl/beta-regression

I cannot tell if there exists a work-around within the sklearn framework.