import os

root_dir = './src/main/resources/omni_power'  # current directory
pattern = '*.json'  # file extension or pattern
assets_txt = './src/main/resources/omni_power/assets.txt'  # current directory

files = []
for dirpath, dirnames, filenames in os.walk(root_dir):
    for filename in filenames:
        if fnmatch.fnmatch(filename, pattern):
            files.append(os.path.join(dirpath, filename))

print(files)