Super Reduced String HackerRank Solution ( Efficient )

Super Reduced String 3.py

def superReducedString(s):
    stack=["#"]         #Initializing the stack with special character because if there are no elements and we access the top of stack it results into IndexError
    for i in s:
        if stack[-1]==i:    #If the element is same as top of stack
            stack.pop()     #Pop the last element and do not push current element
        else:
            stack.append(i)     #Else push the element in the stack
    ans=""
    for i in stack[1:]:     #Ignoring the first index
        ans+=i              #Store the answer in the variable 'ans'
    if ans:
        return ans          #If string is not empty return it
    return "Empty String"   #Else return "Empty String"