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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 populate_template_combobox(self, path, unwanted_templates=None):
 """Helper method for populating template combobox. :param unwanted_templates: List of templates that isn't an option. :type unwanted_templates: list .. versionadded: 4.3.0 """

        templates_dir = QtCore.QDir(path)
        templates_dir.setFilter(
            QtCore.QDir.Files
            | QtCore.QDir.NoSymLinks
            | QtCore.QDir.NoDotAndDotDot)
        templates_dir.setNameFilters(['*.qpt', '*.QPT'])
        report_files = templates_dir.entryList()
        if not unwanted_templates:
            unwanted_templates = []
        for unwanted_template in unwanted_templates:
            if unwanted_template in report_files:
                report_files.remove(unwanted_template)

        for f in report_files:
            self.template_combo.addItem(
                QtCore.QFileInfo(f).baseName(), path + '/' + f)