When I install frappe ( version-13 ) on linux

when I run `bench init`

it gives an error

> 
> ERROR: httplib2 0.20.1 has requirement pyparsing<3,>=2.4.2, but you'll have pyparsing 3.0.0 which is incompatible.
> 
> 
> 

though the installation goes through.

After that when a new site is created it gives an error

> 
> AttributeError: module 'pyparsing' has no attribute 'downcaseTokens
> 
> 
> 

which is a deprecated function not available in version 3.0 but available in 2.4.2

How do I get around this issue ? Can I force install an earlier version of pyparsing ?

Regards
Hari