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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 _meta_from_regex(self, m):
 """Extract and parse YAML metadata from a meta match Notebook metadata must appear at the beginning of the file and follows the Jekyll front-matter convention of dashed delimiters: --- some: yaml --- Cell metadata follows the YAML spec of dashes and periods --- some: yaml Both must be followed by at least one blank line (\n\n). """

        body = m.group('body')
        is_notebook = m.group('sep_close') == '---'

        if is_notebook:
            # make it into a valid YAML object by stripping ---
            body = body.strip()[:-3] + '...'
        try:
            if body:
                return self._meta(yaml.safe_load(m.group('body')), is_notebook)
            else:
                return self._meta({'ipymd': {'empty_meta': True}}, is_notebook)
        except Exception as err:
            raise Exception(body, err)