new_contents: from angr.procedures.stubs.format_parser import FormatParser
  
  from cle.backends.externs.simdata.io_file import io_file_data_for_arch
  
  class fscanf(FormatParser):
      #pylint:disable=arguments-differ
  
      def run(self, file_ptr):
          # TODO handle errors
  
          fd_offset = io_file_data_for_arch(self.state.arch)['fd']
          fd = self.state.mem[file_ptr + fd_offset:].int.resolved
          simfd = self.state.posix.get_fd(fd)
          if simfd is None:
              return -1
  
          fmt_str = self._parse(1)
          items = fmt_str.interpret(2, self.arg, simfd=simfd)
          return items
  
subject: Add fscanf simprocedure