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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(pii_csv, keys, schema, clk_json, quiet, no_header, check_header, validate):
 """Process data to create CLKs Given a file containing CSV data as PII_CSV, and a JSON document defining the expected schema, verify the schema, then hash the data to create CLKs writing them as JSON to CLK_JSON. Note the CSV file should contain a header row - however this row is not used by this tool. It is important that the keys are only known by the two data providers. Two words should be provided. For example: $clkutil hash pii.csv horse staple pii-schema.json clk.json Use "-" for CLK_JSON to write JSON to stdout. """


    schema_object = clkhash.schema.from_json_file(schema_file=schema)
    header = True
    if not check_header:
        header = 'ignore'
    if no_header:
        header = False

    try:
        clk_data = clk.generate_clk_from_csv(
            pii_csv, keys, schema_object,
            validate=validate,
            header=header,
            progress_bar=not quiet)
    except (validate_data.EntryError, validate_data.FormatError) as e:
        msg, = e.args
        log(msg)
        log('Hashing failed.')
    else:
        json.dump({'clks': clk_data}, clk_json)
        if hasattr(clk_json, 'name'):
            log("CLK data written to {}".format(clk_json.name))