message: Update api_def_Zeta.pbtxt
diff: op {
  graph_op_name: "Zeta"
  - summary: "Compute the Hurwitz zeta function \\(\zeta(x, q)\\)."
  + summary: "Compute the Hurwitz zeta function \\\\(\\zeta(x, q)\\\\)."
  description: <<END
  The Hurwitz zeta function is defined as:
  