[python] filedialog, tkinter and opening files

I'm working for the first time on coding a Browse button for a program in Python3. I've been searching the internet and this site, and even python standard library.

I have found sample code and very superficial explanations of things, but I haven't been able to find anything that addresses the problem I'm having directly, or a good enough explanation so I can customize code to my needs.

Here is the relevant snippet:

Button(self, text = "Browse", command = self.load_file, width = 10)\
        .grid(row = 1, column = 0, sticky = W) .....


 def load_file(self):

    filename = filedialog.askopenfilename(filetypes = (("Template files", "*.tplate")
                                                         ,("HTML files", "*.html;*.htm")
                                                         ,("All files", "*.*") ))
    if filename: 
        try: 
            self.settings["template"].set(filename)
        except: 
            messagebox.showerror("Open Source File", "Failed to read file \n'%s'"%filename)
            return

The method is a hybrid of some code I found along the way with my own customizations. It seems like I finally got it to work (kinda), though its not exactly how I need it.

I get this error when I activate the 'Browse' button: NameError: global name 'filedialog' is not defined.

I've found fairly similar issues along the way but all the solutions suggested I have covered. I went into the 'filedialog' help section of IDLE but didn't glean anything from there either.

Would someone mind providing a break down and a little guidance on this; none of my books address it specifically, and I've checked all the solutions provided to others—I'm lost.

I had to specify individual commands first and then use the * to bring all in command.

from tkinter import filedialog
from tkinter import *

Did you try adding the self prefix to the fileName and replacing the method above the Button ? With the self, it becomes visible between methods.

...

def load_file(self):
    self.fileName = filedialog.askopenfilename(filetypes = (("Template files", "*.tplate")
                                                     ,("HTML files", "*.html;*.htm")
                                                     ,("All files", "*.*") ))
...