def get_container_metadata(self, container_name, lease_id=None, timeout=None):
_validate_not_none('<STR_LIT>', container_name)<EOL>request = HTTPRequest()<EOL>request.method = '<STR_LIT:GET>'<EOL>request.host_locations = self._get_host_locations(secondary=True)<EOL>request.path = _get_path(container_name)<EOL>request.query = {<EOL>'<STR_LIT>': '<STR_LIT>',<EOL>'<STR_LIT>': '<STR_LIT>',<EOL>'<STR_LIT>': _int_to_str(timeout),<EOL>}<EOL>request.headers = {'<STR_LIT>': _to_str(lease_id)}<EOL>return self._perform_request(request, _parse_metadata)<EOL>
Returns all user-defined metadata for the specified container.

:param str container_name:
    Name of existing container.
:param str lease_id:
    If specified, get_container_metadata only succeeds if the
    container's lease is active and matches this ID.
:param int timeout:
    The timeout parameter is expressed in seconds.
:return:
    A dictionary representing the container metadata name, value pairs.
:rtype: dict(str, str)