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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 _filehash(filepath, blocksize=4096):
 """ Return the hash object for the file `filepath', processing the file by chunk of `blocksize'. :type filepath: str :param filepath: Path to file :type blocksize: int :param blocksize: Size of the chunk when processing the file """

    sha = hashlib.sha256()
    with open(filepath, 'rb') as fp:
        while 1:
            data = fp.read(blocksize)
            if data:
                sha.update(data)
            else:
                break
    return sha