Identifying a function I am reading a piece of a physic paper where a function is mentioned without being given a name or reference - I guess it is a canonical one and that I should be familiar with. The expression goes as: $$|_2F_1(a,b;c;z)|$$ with $a,b,c \in {\mathbb R}$ and $z \in {\mathbb C}$. Also I am fairly sure the lowerscript 2 is a label on the function.

This is probably the hypergeometric function.