(Eugene, OR)  --  A former Eugene elementary school teacher is pleading guilty to sexually abusing a child.  Court records show 38-year-old William Hamman pleaded guilty yesterday to one count of sex trafficking of a child.  Hamman used social media to arrange meeting with the girl in 2018.  Police arrested him in 2019 and found video of one of the assaults on his phone.  Sentencing is set for March 1st.