os module

import os

def folder_contains_file(folder_path, file_name):
    for file in os.listdir(folder_path):
        if file == file_name:
            return True
    return False

# Test
folder_path = "/path/to/your/folder"
file_name = "example.txt"
print(folder_contains_file(folder_path, file_name))  # True or False

pathlib module

from pathlib import Path

def folder_contains_file(folder_path, file_name):
    folder = Path(folder_path)
    for file in folder.iterdir():
        if file.name == file_name:
            return True
    return False

# Test
folder_path = "/path/to/your/folder"
file_name = "example.txt"
print(folder_contains_file(folder_path, file_name))  # True or False