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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 hash_file(path, block_size=65536):
 """Returns SHA256 checksum of a file Args: path (string):
 Absolute file path of file to hash block_size (int, optional):
 Number of bytes to read per block """

    sha256 = hashlib.sha256()
    with open(path, 'rb') as f:
        for block in iter(lambda: f.read(block_size), b''):
            sha256.update(block)
    return sha256.hexdigest()