<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def expand_name(self, flag):
 """ Complete a flag for this endpoint by expanding the endpoint name. If the flag does not already contain ``{endpoint_name}``, it will be prefixed with ``endpoint.{endpoint_name}.``. Then, any occurance of ``{endpoint_name}`` will be replaced with ``self.endpoint_name``. """

        if '{endpoint_name}' not in flag:
            flag = 'endpoint.{endpoint_name}.' + flag
        # use replace rather than format to prevent any other braces or braced
        # strings from being touched
        return flag.replace('{endpoint_name}', self.endpoint_name)