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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 _is_partial_index(gbi_file):
 """Check for truncated output since grabix doesn't write to a transactional directory. """

    with open(gbi_file) as in_handle:
        for i, _ in enumerate(in_handle):
            if i > 2:
                return False
    return True