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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 delete_permission(self, vname, username):
 """ Delete permission for a given username on a given vhost. Both must already exist. :param string vname: Name of the vhost to set perms on. :param string username: User to set permissions for. """

        vname = quote(vname, '')
        path = Client.urls['vhost_permissions'] % (vname, username)
        return self._call(path, 'DELETE')