Binary Search is a lot faster than linear search

#standard linear search
def linear_search(itemList, searchFor, startIndex=0, endIndex=None):
   for item in itemList:
       if item == searchFor:
           return item
   return None

#fast binary search
def binary_search(itemList, searchFor, startIndex=0, endIndex=None):
   if endIndex is None:
       endIndex = len(itemList)
   while startIndex < endIndex:
       mid = (startIndex + endIndex)//2
       midval = itemList[mid]
       if midval < searchFor:
           startIndex = mid+1
       elif midval > searchFor:
           endIndex = mid
       else:
           return mid
   return None

#test script

import random
import time
testList = [n for n in range(10000000)]
testValue = random.randint(0,10000000)

startTime = time.time()
print linear_search(testList, testValue)
elapse = time.time() - startTime

print "Linear [ms]", elapse * 1000.0

startTime = time.time()
print binary_search(testList, testValue)
elapse = time.time() - startTime
print "Binary [ms]", elapse * 1000.0

#console output

6757414
Linear [ms] 326.999902725
6757414
Binary [ms] 0.0