'expands the volume to new_size specified.'

@retry_wrapper
def expand_volume(self, vol, new_size):

    self.authenticate_user()
    volume_name = self._get_coprhd_volume_name(vol)
    size_in_bytes = coprhd_utils.to_bytes(('%sG' % new_size))
    try:
        self.volume_obj.expand(('%s/%s' % (self.configuration.coprhd_tenant, self.configuration.coprhd_project)), volume_name, size_in_bytes, True)
    except coprhd_utils.CoprHdError as e:
        coprhd_err_msg = (_('Volume    %(volume_name)s:    expand    failed\n%(err)s') % {'volume_name': volume_name, 'err': six.text_type(e.msg)})
        log_err_msg = ('Volume    :    %s    expand    failed' % volume_name)
        self._raise_or_log_exception(e.err_code, coprhd_err_msg, log_err_msg)
