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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_small_vcf(vcf_file):
 """Check for small VCFs which we want to analyze quicker. """

    count = 0
    small_thresh = 250
    with utils.open_gzipsafe(vcf_file) as in_handle:
        for line in in_handle:
            if not line.startswith("#"):
                count += 1
            if count > small_thresh:
                return False
    return True