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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 classify_format(f):
 """ Determine the format of word embedding file by their content. This operation only looks at the first two lines and does not check the sanity of input file. Args: f (Filelike):
 Returns: class """

    l0, l1 = _get_two_lines(f)
    if loader.glove.check_valid(l0, l1):
        return _glove
    elif loader.word2vec_text.check_valid(l0, l1):
        return _word2vec_text
    elif loader.word2vec_bin.check_valid(l0, l1):
        return _word2vec_bin
    else:
        raise OSError(b"Invalid format")