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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 validateSQL(self, sql, sqlType="where"):
 """ The validateSQL operation validates an SQL-92 expression or WHERE clause. The validateSQL operation ensures that an SQL-92 expression, such as one written by a user through a user interface, is correct before performing another operation that uses the expression. For example, validateSQL can be used to validate information that is subsequently passed in as part of the where parameter of the calculate operation. validateSQL also prevents SQL injection. In addition, all table and field names used in the SQL expression or WHERE clause are validated to ensure they are valid tables and fields. Inputs: sql - The SQL expression or WHERE clause to validate. sqlType - Three SQL types are supported in validateSQL: where (default) - Represents the custom WHERE clause the user can compose when querying a layer or using calculate. expression - Represents an SQL-92 expression. Currently, expression is used as a default value expression when adding a new field or using the calculate API. statement - Represents the full SQL-92 statement that can be passed directly to the database. No current ArcGIS REST API resource or operation supports using the full SQL-92 SELECT statement directly. It has been added to the validateSQL for completeness. Values: where | expression | statement """

        url = self._url + "/validateSQL"
        if not sqlType.lower() in ['where', 'expression', 'statement']:
            raise Exception("Invalid Input for sqlType: %s" % sqlType)
        params = {
            "f" : "json",
            "sql" : sql,
            "sqlType" : sqlType
        }
        return self._post(url=url,
                             param_dict=params,
                             securityHandler=self._securityHandler,
                             proxy_url=self._proxy_url,
                             proxy_port=self._proxy_port)