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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 update_record_field(table, sys_id, field, value):
    '''
    Update the value of a record's field in a servicenow table

    :param table: The table name, e.g. sys_user
    :type  table: ``str``

    :param sys_id: The unique ID of the record
    :type  sys_id: ``str``

    :param field: The new value
    :type  field: ``str``

    :param value: The new value
    :type  value: ``str``

    CLI Example:

    .. code-block:: bash

        salt myminion servicenow.update_record_field sys_user 2348234 first_name jimmy
    '''
    client = _get_client()
    client.table = table
    response = client.update({field: value}, sys_id)
    return response