Tkinter is a great package and filedialog has some very helpful features. Both askopenfilename and asksaveasfilename have the 'filetypes' attribute, but it works differently for each one. 

With askopenfilename it provides options in the GUI and returns the filetype, BUT

with asksaveasfilename it only provides options in the GUI and does not return the filetype. Example code is shown below:

```
import tkinter as tk 
from tkinter import filedialog 

old_file_name = filedialog.askopenfilename(title = "Choose file",filetypes=\
                                       (('All files','*.*'),\
                                        ('tagData','*.tagData'),\
                                        ('FDAX files','*.fdax'),\
                                        ('CSV files','*.csv')))

new_file_name = filedialog.asksaveasfilename(initialdir = "/",filetypes=\
                                         (('tagData','*.tagData'),\
                                          ('FDAX files','*.fdax'),\
                                          ('CSV files','*.csv'),\
                                          ('XLS files','*.xls')))

print(old_file_name)
print(new_file_name)

```

Output:

```
 C:/Users/christian.abbott/Desktop/FDAX_Error/example.csv
 C:/Users/christian.abbott/Desktop/example

```

I have looked for good filedialog documentation but have not been able to find it. Why does the package behave this way? Is there a better option to extract the full path of a user-prompted file path?