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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 _get_md_files(self):
 """Get all markdown files."""

        all_f = _all_files_matching_ext(os.getcwd(), "md")
        exclusions = [
            "*.egg/*",
            "*.eggs/*",
            "*build/*"
        ] + self.exclusions
        return sorted([f for f in all_f if not _is_excluded(f, exclusions)])