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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 _find_library_candidates(library_names, library_file_extensions, library_search_paths):
 """ Finds and returns filenames which might be the library you are looking for. """

    candidates = set()
    for library_name in library_names:
        for search_path in library_search_paths:
            glob_query = os.path.join(search_path, '*'+library_name+'*')
            for filename in glob.iglob(glob_query):
                filename = os.path.realpath(filename)
                if filename in candidates:
                    continue
                basename = os.path.basename(filename)
                if basename.startswith('lib'+library_name):
                    basename_end = basename[len('lib'+library_name):]
                elif basename.startswith(library_name):
                    basename_end = basename[len(library_name):]
                else:
                    continue
                for file_extension in library_file_extensions:
                    if basename_end.startswith(file_extension):
                        if basename_end[len(file_extension):][:1] in ('', '.'):
                            candidates.add(filename)
                    if basename_end.endswith(file_extension):
                        basename_middle = basename_end[:-len(file_extension)]
                        if all(c in '0123456789.' for c in basename_middle):
                            candidates.add(filename)
    return candidates