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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_files (self):
 """Get list of filenames in directory. Subdirectories have an ending slash."""

        files = []
        def add_entry (line):
            """Parse list line and add the entry it points to to the file
            list."""
            log.debug(LOG_CHECK, "Directory entry %r", line)
            from ..ftpparse import ftpparse
            fpo = ftpparse(line)
            if fpo is not None and fpo["name"]:
                name = fpo["name"]
                if fpo["trycwd"]:
                    name += "/"
                if fpo["trycwd"] or fpo["tryretr"]:
                    files.append(name)
        self.url_connection.dir(add_entry)
        return files