class_docstr: Abstract base class for all implemented policies.
  
  Each policy helps with selection of action to take on an environment.
  
  Do not use this abstract base class directly but instead use one of the concrete policies implemented.
  To implement your own policy, you have to implement the following methods:
  
  - `select_action`
  
  # Arguments
      agent (rl.core.Agent): Agent used
class_docstr_tok: ["Abstract","base","class","for","all","implemented","policies",".","Each","policy","helps","with","selection","of","action","to","take","on","an","environment",".","Do","not","use","this","abstract","base","class","directly","but","instead","use","one","of","the","concrete","policies","implemented",".","To","implement","your","own","policy",",","you","have","to","implement","the","following","methods",":","-","`","select_action","`","#","Arguments","agent","(","rl.core.Agent",")",":","Agent","used"]
code: def select_action(self, **kwargs):
      raise NotImplementedError()
  
imports: from __future__ import division
  import numpy
  from rl.util import *
label_desc: Use image node_id 4 for calling the Policy obj's underlying member method code with example usage: obj.select_action() without return types