leetcode225.py
def push(self, x):
        """
        Push element x onto stack.
        :type x: int
        :rtype: void
        """

        Push element x onto stack.
        :type x: int
        :rtype: void
        
Push element x onto stack.
Push element x onto stack .
def push(self, x):
def push ( self , x ) :
Push element x onto stack.
Push element x onto stack .
"""
        Push element x onto stack.
        :type x: int
        :rtype: void
        """
None
void
self
x