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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 calculate(self, where, calcExpression, sqlFormat="standard"):
 """ The calculate operation is performed on a feature service layer resource. It updates the values of one or more fields in an existing feature service layer based on SQL expressions or scalar values. The calculate operation can only be used if the supportsCalculate property of the layer is true. Neither the Shape field nor system fields can be updated using calculate. System fields include ObjectId and GlobalId. See Calculate a field for more information on supported expressions Inputs: where - A where clause can be used to limit the updated records. Any legal SQL where clause operating on the fields in the layer is allowed. calcExpression - The array of field/value info objects that contain the field or fields to update and their scalar values or SQL expression. Allowed types are dictionary and list. List must be a list of dictionary objects. Calculation Format is as follows: {"field" : "<field name>", "value" : "<value>"} sqlFormat - The SQL format for the calcExpression. It can be either standard SQL92 (standard) or native SQL (native). The default is standard. Values: standard, native Output: JSON as string Usage: securityHandler=sh, initialize=True) calcExpression={"field": "ZONE", "value" : "R1"}) {'updatedFeatureCount': 1, 'success': True} """

        url = self._url + "/calculate"
        params = {
            "f" : "json",
            "where" : where,

        }
        if isinstance(calcExpression, dict):
            params["calcExpression"] = json.dumps([calcExpression],
                                                  default=_date_handler)
        elif isinstance(calcExpression, list):
            params["calcExpression"] = json.dumps(calcExpression,
                                                  default=_date_handler)
        if sqlFormat.lower() in ['native', 'standard']:
            params['sqlFormat'] = sqlFormat.lower()
        else:
            params['sqlFormat'] = "standard"
        return self._post(url=url,
                             param_dict=params,
                             securityHandler=self._securityHandler,
                             proxy_port=self._proxy_port,
                             proxy_url=self._proxy_url)