Add strcspn in tools

import urllib2

from subprocess import call, check_call, CalledProcessError

from itertools import takewhile

import installsystems

from progressbar import Widget, ProgressBar, Percentage

        return [unicode(x, encoding=locale.getpreferredencoding()) for x in sys.argv]

    except UnicodeDecodeError as e:

        raise ISError("Invalid character encoding in command line")

def strcspn(string, pred):

    '''

    Python implementation of libc strcspn

    '''

    return len(list(takewhile(lambda x: x not in pred, string)))