import sys
import os
import string
import re
import random

def escape(s): 
   """This is a utility function to escape and return a string."""
   s = string.replace(s, '\t', '\\t')
   s = string.replace(s, '"', '\\"')
   s = string.replace(s, '\n', '\\n')
   s = string.replace(s, '\r', '\\r')
   s = string.replace(s, '\\', '\\\\')
   return s

def unescape(s): 
   """This is a utility function to unescape and return a string."""
   s = string.replace(s, '\\t', '\t')
   s = string.replace(s, '\\"', '"')
   s = string.replace(s, '\\n', '\n')
   s = string.replace(s, '\\r', '\r')
   s = string.replace(s, '\\\\', '\\')
   return s

def generatecontext(): 
   """Generates an alphanum string with 351,964,250,202,852,352 combinations."""
   anchrs, achrs = [], []
   anstr = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
   astr = 'abcdefghijklmnopqrstuvwxyz'
   for c in anstr: anchrs.append(c)
   for c in astr: achrs.append(c)
   a = random.choice(achrs)+random.choice(anchrs)+random.choice(anchrs)
   b = random.choice(anchrs)+random.choice(anchrs)+random.choice(anchrs)
   c = random.choice(anchrs)+random.choice(anchrs)+random.choice(anchrs)
   d = random.choice(anchrs)
   return a+b+c+d # 10 characters, makes a valid bnode

def generateint(): 
   return str(random.randrange(0,9,1))

def uri2qname(s): 
   # print str(s)
   if '#' in s: 
      x = string.split(s, '#')
      # print str(x)
      return [x[0]+'#',x[1]]
   else: return [s[:-1],s[-1]]