Implementation of HashTable in Python - Extracted from http://interactivepython.org/runestone/static/pythonds/SortSearch/Hashing.html

HashMap.py

class HashTable:
    def __init__(self):
        self.size = 11
        self.slots = [None] * self.size
        self.data = [None] * self.size
    
    def put(self,key,data):
      hashvalue = self.hashfunction(key,len(self.slots))

      if self.slots[hashvalue] == None:
        self.slots[hashvalue] = key
        self.data[hashvalue] = data
      else:
        if self.slots[hashvalue] == key:#if there was already something at that key,
          self.data[hashvalue] = data  #replace
        else:
          nextslot = self.rehash(hashvalue,len(self.slots))
          while self.slots[nextslot] != None and \
                      self.slots[nextslot] != key:
            nextslot = self.rehash(nextslot,len(self.slots))

          if self.slots[nextslot] == None:
            self.slots[nextslot]=key
            self.data[nextslot]=data
          else:
            self.data[nextslot] = data #replace

    def hashfunction(self,key,size):
      return key%size

    def rehash(self,oldhash,size):
      return (oldhash+1)%size    
      
    def get(self,key):
      startslot = self.hashfunction(key,len(self.slots))
      data = None
      stop = False
      found = False
      position = startslot
      
      while self.slots[position] != None and  \
                       not found and not stop:
        if self.slots[position] == key:
          found = True
          data = self.data[position]
        else:
          position=self.rehash(position,len(self.slots))
          if position == startslot:
              stop = True
      return data

    def __getitem__(self,key):
      return self.get(key)

    def __setitem__(self,key,data):
      self.put(key,data)