{
"external_userid": "string"
}curl --location -g --request POST '/cgi-bin/externalcontact/convert_to_openid?access_token={{accesstoken}}' \
--header 'Content-Type: application/json' \
--data-raw '{
"external_userid": "string"
}'{
"errcode": 0,
"openid": "string",
"errmsg": "string"
}