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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 _write(self, context, report_dir, report_name, assets_dir=None, template=None):
 """Writes the data in `context` in the report's template to `report_name` in `report_dir`. If `assets_dir` is supplied, copies all assets for this report to the specified directory. If `template` is supplied, uses that template instead of automatically finding it. This is useful if a single report generates multiple files using the same template. :param context: context data to render within the template :type context: `dict` :param report_dir: directory to write the report to :type report_dir: `str` :param report_name: name of file to write the report to :type report_name: `str` :param assets_dir: optional directory to output report assets to :type assets_dir: `str` :param template: template to render and output :type template: `jinja2.Template` """

        if template is None:
            template = self._get_template()
        report = template.render(context)
        output_file = os.path.join(report_dir, report_name)
        with open(output_file, 'w', encoding='utf-8') as fh:
            fh.write(report)
        if assets_dir:
            self._copy_static_assets(assets_dir)