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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 add_custom_field_setting(self, project, params={}, **options):
 """Create a new custom field setting on the project. Parameters project : {Id} The project to associate the custom field with [data] : {Object} Data for the request - custom_field : {Id} The id of the custom field to associate with this project. - [is_important] : {Boolean} Whether this field should be considered important to this project. - [insert_before] : {Id} An id of a Custom Field Settings on this project, before which the new Custom Field Settings will be added. `insert_before` and `insert_after` parameters cannot both be specified. - [insert_after] : {Id} An id of a Custom Field Settings on this project, after which the new Custom Field Settings will be added. `insert_before` and `insert_after` parameters cannot both be specified. """

        path = "/projects/%s/addCustomFieldSetting" % (project)
        return self.client.post(path, params, **options)