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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 chdir(self, directory_path, make=False):
 """Change directories and optionally make the directory if it doesn't exist."""

        if os.sep in directory_path:
            for directory in directory_path.split(os.sep):
                if make and not self.directory_exists(directory):
                    try:
                        self.session.mkd(directory)
                    except ftplib.error_perm:
                        # Directory already exists
                        pass
                self.session.cwd(directory)
        else:
            self.session.cwd(directory_path)