title: PostgreSQL Syntax error at or near FUNCTION on create trigger
body: <p>I installed postgresql and postgresql-plpython-10 (using apt) on a new machine running Ubuntu server 18.04
  and I have reinstated a Postgresql database (extracted using <code>pg_dumpall</code>) from another machine onto a new machine (Linux).</p>
  
  <p>I checked that the trackspreadsheetnztplpy function exists in the database and the table nztgsheet exists. I reran the function on the old machine and it worked perfectly. I checked plpythonu is installed on the new machine using psql command: <code>\dL</code>.</p>
  
  <p>SQL error:</p>
  
  <p>ERROR:  syntax error at or near "FUNCTION"
  LINE 1: ...H ROW WHEN (OLD.* IS DISTINCT FROM NEW.*) EXECUTE FUNCTION t...
                                                               ^</p>
  
  <p>In statement:
  <code>CREATE TRIGGER trackspreadsheetnzt AFTER UPDATE ON nztgsheet FOR EACH ROW WHEN (OLD.* IS DISTINCT FROM NEW.*) EXECUTE FUNCTION trackspreadsheetnztplpy();</code></p>
  
  <p>I expected the trigger function to work, but it throws a syntax error instead.</p>