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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 unique_hash(filepath: str, blocksize: int=80)->str: """ Small function to generate a hash to uniquely generate a file. Default blocksize is `500` """

    s = sha1()
    with open(filepath, "rb") as f:
        buf = f.read(blocksize)
        s.update(buf)
    return s.hexdigest()