'Sets a threshold for concurrent requests per connection, below which
connections will be considered for disposal (down to core connections;
see :meth:`~Cluster.set_core_connections_per_host`).
Pertains to connection pool management in protocol versions {1,2}.'

def set_min_requests_per_connection(self, host_distance, min_requests):

    if (self.protocol_version >= 3):
        raise UnsupportedOperation('Cluster.set_min_requests_per_connection()    only    has    an    effect    when    using    protocol_version    1    or    2.')
    if ((min_requests < 0) or (min_requests > 126) or (min_requests >= self._max_requests_per_connection[host_distance])):
        raise ValueError(('min_requests    must    be    0-126    and    less    than    the    max_requests    for    this    host_distance    (%d)' % (self._min_requests_per_connection[host_distance],)))
    self._min_requests_per_connection[host_distance] = min_requests
