(self)
expands size of the array.
         Time Complexity: O(n)
expands size of the array.
         Time Complexity: O(n)
expands size of the array . Time Complexity : O ( n )
def _expand(self):
        """
         expands size of the array.
         Time Complexity: O(n)
        """
        self._array += [None] * len(self._array)
def _expand ( self ) : self . _array += [ None ] * len ( self . _array )