deletions | additions       diff --git a/header.tex b/header.tex  index 383d6be..578b7d0 100644  --- a/header.tex  +++ b/header.tex 
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\usepackage{amssymb}  \usepackage{amsthm}  \newtheorem{theorem}{Theorem}  \newtheorem{proof}{Proof}  \usepackage{thmtools}