reload_on = False #reload from external file or save all from internal
import bpy
area = bpy.context.area
for text in bpy.data.texts:
    area.spaces[0].text = text
    if text.filepath != '' and reload_on == True:
        bpy.ops.text.reload()
    if text.filepath != '' and text.is_dirty:
        bpy.ops.text.save()