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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 parse_ftype(input_file):
 """ Checks determine filetype from extension. :param str input_file: String to check. :return str: filetype (extension without dot prefix) :raises TypeError: if file does not appear of a supported type """

    if input_file.endswith(".bam"):
        return "bam"
    elif input_file.endswith(".fastq") or \
            input_file.endswith(".fq") or \
            input_file.endswith(".fq.gz") or \
            input_file.endswith(".fastq.gz"):
        return "fastq"
    else:
        raise TypeError("Type of input file ends in neither '.bam' "
                        "nor '.fastq' [file: '" + input_file + "']")