local p = {}  require "mw.ustring"  function p.remove_parents( frame )      str = frame.args.string      gsub = mw.ustring.gsub            str=gsub(str, " *[(].*[)]","")      return str       end  function p.only_parents_contents( frame )      str = frame.args.string      match = mw.ustring.match      gsub = mw.ustring.gsub            str=p.remove_sq_parents_internal(str)      str=match(str, "%b()$") -- a(b) ==> (b) or nil      if (str == nil) then return "" end       str=gsub(str,"^%((.*)%)$", "%1") -- (b) ==> b      return str       end  function p.remove_sq_parents_internal( str )      gsub = mw.ustring.gsub            str=gsub(str, "^%[%[(.*)%|.*%]%]$","%1") -- [[x|y]] ==> x      str=gsub(str, "^%[%[(.*)%]%]$","%1") -- [[x]] ==> x      return str       end  function p.remove_sq_parents( frame )      str = frame.args.string      return p.remove_sq_parents_internal(str)       end   return p