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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 _load_lib():
 """Load LightGBM library."""

    lib_path = find_lib_path()
    if len(lib_path) == 0:
        return None
    lib = ctypes.cdll.LoadLibrary(lib_path[0])
    lib.LGBM_GetLastError.restype = ctypes.c_char_p
    return lib