<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def permissions(self):
 """ Permissions of the file. Can be "r-" (read-only), "-w" (write-only), "rw" (read-write) or "--" (no rights). :rtype: str """

        can_read = self._info.file.permissions & lib.GP_FILE_PERM_READ
        can_write = self._info.file.permissions & lib.GP_FILE_PERM_DELETE
        return "{0}{1}".format("r" if can_read else "-",
                               "w" if can_write else "-")