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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 create(self, language, query, tasks=values.unset, model_build=values.unset, field=values.unset):
 """ Create a new QueryInstance :param unicode language: An ISO language-country string of the sample. :param unicode query: A user-provided string that uniquely identifies this resource as an alternative to the sid. It can be up to 2048 characters long. :param unicode tasks: Constraints the query to a set of tasks. Useful when you need to constrain the paths the user can take. Tasks should be comma separated task-unique-name-1, task-unique-name-2 :param unicode model_build: The Model Build Sid or unique name of the Model Build to be queried. :param unicode field: Constraints the query to a given Field with an task. Useful when you know the Field you are expecting. It accepts one field in the format task-unique-name-1:field-unique-name :returns: Newly created QueryInstance :rtype: twilio.rest.preview.understand.assistant.query.QueryInstance """

        data = values.of({
            'Language': language,
            'Query': query,
            'Tasks': tasks,
            'ModelBuild': model_build,
            'Field': field,
        })

        payload = self._version.create(
            'POST',
            self._uri,
            data=data,
        )

        return QueryInstance(self._version, payload, assistant_sid=self._solution['assistant_sid'], )