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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 fromGeoCoordinateString(self, sr, strings, conversionType, conversionMode=None):
 """ The fromGeoCoordinateString operation is performed on a geometry service resource. The operation converts an array of well-known strings into xy-coordinates based on the conversion type and spatial reference supplied by the user. An optional conversion mode parameter is available for some conversion types. Inputs: sr - The well-known ID of the spatial reference or a spatial reference json object. strings - An array of strings formatted as specified by conversionType. Example: ["01N AA 66021 00000","11S NT 00000 62155", "31U BT 94071 65288"] conversionType - The conversion type of the input strings. Valid conversion types are: MGRS - Military Grid Reference System USNG - United States National Grid UTM - Universal Transverse Mercator GeoRef - World Geographic Reference System GARS - Global Area Reference System DMS - Degree Minute Second DDM - Degree Decimal Minute DD - Decimal Degree conversionMode - Conversion options for MGRS, UTM and GARS conversion types. Conversion options for MGRS and UTM conversion types. Valid conversion modes for MGRS are: mgrsDefault - Default. Uses the spheroid from the given spatial reference. mgrsNewStyle - Treats all spheroids as new, like WGS 1984. The 180 degree longitude falls into Zone 60. mgrsOldStyle - Treats all spheroids as old, like Bessel 1841. The 180 degree longitude falls into Zone 60. mgrsNewWith180InZone01 - Same as mgrsNewStyle except the 180 degree longitude falls into Zone 01. mgrsOldWith180InZone01 - Same as mgrsOldStyle except the 180 degree longitude falls into Zone 01. Valid conversion modes for UTM are: utmDefault - Default. No options. utmNorthSouth - Uses north/south latitude indicators instead of zone numbers. Non-standard. Default is recommended """

        url = self._url + "/fromGeoCoordinateString"
        params = {
            "f" : "json",
            "sr" : sr,
            "strings" : strings,
            "conversionType" : conversionType
        }
        if not conversionMode is None:
            params['conversionMode'] = conversionMode
        return self._post(url=url, param_dict=params,
                             securityHandler=self._securityHandler,
                             proxy_url=self._proxy_url,
                             proxy_port=self._proxy_port)