seq.py 文件源码

def count_records(input_object, format='fasta'):
    """Count SeqRecord objects from a file in the specified format.

    :param input_object: A file object or a file name.
    :param format: Input format (fasta by default).
    :returns: Number of records in input file.
    :rtype: int

    """
    handle = input_object
    if type(handle) == str:
        handle = open(handle, "rU")
    counter = 0
    for _ in SeqIO.parse(handle, format):
        counter += 1
    return counter