PYTHONSTARTUP
  If this is the name of a readable file, the Python commands in that file are executed before the first prompt is displayed in interactive mode. The file is executed in the same name space where interactive commands are executed so that objects defined or imported in it can be used without qualification in the interactive session. You can also change the prompts sys.ps1 and sys.ps2 in this file.

~/.bashrc

  export PYTHONSTARTUP=~/.pythonstartup.py

~/.pythonstartup.py

  import readline, rlcompleter        
  readline.parse_and_bind("tab: complete")                                 
  import os, sys
  def cc() :
    os.system('clear')