how to search folder for file in python code example

Example: python find file in directory

# option A (i think this is faster, not in micropython)

import os

if os.path.isfile("test.dat"):
	print("yes") #file found
else:
	print("no") #file not found

# also this is posible
# from os.path import isfile
# if isfile("test.dat"):


# option B (posible in micropython)

import os

if "test.dat" in os.listdir():
	print("yes") # file found
else:
	print("no") # file not found

# os.lisdir() return a array whit all the files found in the directory