Writing a function that accepts a path to an input file

[says]

import os
path = 'c:\users\name\desktop\project\input_samples'

for xyz_file in os.listdir(path):
    if xyz_file.endswith('xyz'):
    (operations of function here)

In the folder 'input samples' I have multiple .xyz file (coordinate files). I'm trying to create a function that accepts a path to one input file and not the directory. It don't want it to loop over the files, just process a single file. I want to do it without having to remove all the files except 1 in the directory path.

Any help would be much appreciated :)

[Larz60+]

add \yourfilename after existing path

[says]

that results in an error for line 4

WindowsError: [Error 267] The directory name is invalid: 'c:\\users\\sammy\\desktop\\NanoNet\\input_samples\\SiNW2.xyz\\*.*'

[buran]

why add \\*.* at the end?
you claim you want single file. That is SiNW2.xyz, right? In this case just 'c:\\users\\sammy\\desktop\\NanoNet\\input_samples\\SiNW2.xyz' would do.