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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def copy_files(src, ext, dst):
 """ Copies files with extensions "ext" from "src" to "dst" directory. """

    src_path = os.path.join(os.path.dirname(__file__), src)
    dst_path = os.path.join(os.path.dirname(__file__), dst)
    file_list = os.listdir(src_path)
    for f in file_list:
        if f == '__init__.py':
            continue
        f_path = os.path.join(src_path, f)
        if os.path.isfile(f_path) and f.endswith(ext):
            shutil.copy(f_path, dst_path)