          vector (ndarray): The vector to set.
          """
          i = self.key2row[key]
          self.data[i] = vector
          if i in self._unset:
              self._unset.remove(i)
  
      def __iter__(self):
          """Iterate over the keys in the table.
  
          YIELDS (int): A key in the table.
 
</s> remove             if row not in self._unset:
 </s> add             if not self._unset.count(row): </s> remove             if row in self._unset:
                self._unset.remove(row)
 </s> add             if self._unset.count(row):
                self._unset.erase(self._unset.find(row)) </s> remove             row = min(self._unset)
 </s> add             row = deref(self._unset.begin()) </s> remove             self._unset = set(range(self.data.shape[0]))
 </s> add             self._unset = cppset[int]({i for i in range(self.data.shape[0])}) </s> remove         return len(self._unset) == 0
 </s> add         return self._unset.size() == 0
        if self._unset.count(i):
            self._unset.erase(self._unset.find(i))
          vector (ndarray): The vector to set.
          """
          i = self.key2row[key]
          self.data[i] = vector
        if self._unset.count(i):
            self._unset.erase(self._unset.find(i))
        if self._unset.count(i):
            self._unset.erase(self._unset.find(i))
  
      def __iter__(self):
          """Iterate over the keys in the table.
  
          YIELDS (int): A key in the table.
keep keep keep keep replace replace keep keep keep keep keep
 [2032] - Changed python set to cpp stl set (#2170)

Changed python set to cpp stl set #2032 

## Description

Changed python set to cpp stl set. CPP stl set works better due to the logarithmic run time of its methods. Finding minimum in the cpp set is done in constant time as opposed to the worst case linear runtime of python set. Operations such as find,count,insert,delete are also done in either constant and logarithmic time thus making cpp set a better option to manage vectors.
Reference : http://www.cplusplus.com/reference/set/set/

### Types of change
Enhancement for `Vectors` for faster initialising of word vectors(fasttext) 
spacy/vectors.pyx