Error when data is added to file

[nkh]

commands:

speedometer speedometer_test 200

touch speedometer_test
cat > speedometer_test
type type type\n
crashes here

Waiting for 'speedometer_test' to be created...
^[^[:Traceback (most recent call last):
File "/usr/bin/speedometer", line 1094, in
console()
File "/usr/bin/speedometer", line 812, in console
do_display(cols, urwid_ui, exit_on_complete, num_colors)
File "/usr/bin/speedometer", line 817, in do_display
mg.main(num_colors)
File "/usr/bin/speedometer", line 272, in main
self.loop.run()
File "/usr/lib/python3/dist-packages/urwid/main_loop.py", line 287, in run
self._run()
File "/usr/lib/python3/dist-packages/urwid/main_loop.py", line 385, in _run
self.event_loop.run()
File "/usr/lib/python3/dist-packages/urwid/main_loop.py", line 790, in run
self._loop()
File "/usr/lib/python3/dist-packages/urwid/main_loop.py", line 823, in _loop
alarm_callback()
File "/usr/lib/python3/dist-packages/urwid/main_loop.py", line 173, in cb
callback(self, user_data)
File "/usr/bin/speedometer", line 287, in update_callback
pending = self.update_readings()
^^^^^^^^^^^^^^^^^^^^^^
File "/usr/bin/speedometer", line 296, in update_readings
if d.update_readings(): pending += 1
^^^^^^^^^^^^^^^^^^^
File "/usr/bin/speedometer", line 392, in update_readings
self.est.set_text(readable_time(e,10))
^^^^^^^^^^^^^^^^^^^
File "/usr/bin/speedometer", line 761, in readable_time
new_out = new_out + value + suf
~~~~~~~~^~~~~~~
TypeError: can only concatenate str (not "int") to str