python - How does adding tags change a text file - Tkinter? -

i beginner in tkinter , trying create interface, runs program checks 'correctness' of formal specifications. program checks whether written specification meets criteria - checks whether terms used declared, etc.

anyway, trying add search button, changes color of key words, when found in text - use tags , works ok. problem is, after have used search function (i.e. have added tags , removed them, when clicking on save) program checks 'correctness' of specification doesn't run properly, on files have been checked , shown correct. following error:

file "c:\python27\lib\lib-tk\tkinter.py", line 1193, in _configure     self.tk.call(_flatten((self._w, cmd)) + self._options(cnf)) tclerror: invalid command name ".43965456" 

i have no idea might mean. wondering whether adding tags changes text file in way (apart changing color of key words), might mess program, checks 'correctness'.

here search function:

def searchwindowbutton(self,event):          self.top = toplevel()         self.top.title("search")         label(self.top,text='text find:').pack(side=left)         self.edit = entry(self.top)         self.edit.pack(side=left, fill=both, expand=1)         self.edit.focus_set()         button = button(self.top, text="search", command = self.on_button)         button.pack(side=left)       def find(self):          self.txt.tag_remove('found', '1.0', end)         s = self.edit.get()         if s:             idx = '1.0'             while 1:                 idx = self.txt.search(s, idx, nocase=1, stopindex=end)                 if not idx: break                 lastidx = '%s+%dc' % (idx, len(s))                 self.txt.tag_add('found', idx, lastidx)                 idx = lastidx             self.txt.tag_config('found', background='green', foreground='black')         self.edit.focus_set()       def on_button(self):         self.find()         self.top.destroy() 

and save function:

def savemenu(self):         try:             self.txt.tag_remove("found",  "1.0", 'end')             filename=self.fl             fl = open(filename, 'w')             textoutput = self.txt.get(0.0, end)             fl.write(textoutput)         except:             self.save_asmenu() 

i wondering whether adding tags changes text file in way (apart changing color of key words)

no, adding tags has absolutely 0 effect on text file.

tclerror: invalid command name ".43965456" means widget internal id of .43965456 has been destroyed prior calling whatever function triggers error.