String Builder in python

StringBuilder.py

class StringBuilder(object):
    def __init__(self, val):
        self.store = [val]

    def __iadd__(self, value):
        self.store.append(value)
        return self

    def __str__(self):
        return "".join(self.store)
      
#Test
initial = 'value'
stringBuilder = StringBuilder(initial)
for _ in range(2000):
    stringBuilder += 'value'
print(str(stringBuilder))

#Thanks to 
#https://grokbase.com/t/python/python-ideas/118sgkcgg0/create-a-stringbuilder-class-and-use-it-everywhere

Great, but is it possible to create some advanced features?
ex void Clear()

compared to, VS ... such as in
https://www.chilkatsoft.com/refdoc/pythonStringBuilderRef.html

• void Clear()
• bool Append(string value)
• bool Contains(string str, bool caseSensitive)

initial = 'value'
stringBuilder = StringBuilder('')
print(" id {} - string {} \n str(): {} - repr(): {}".format( id(stringBuilder), stringBuilder, repr(stringBuilder), str(stringBuilder)))
stringBuilder +="test"
print(" id {} - string {}\n".format( id(stringBuilder), stringBuilder))
for _ in range(10):
    stringBuilder += 'value'
print(str(stringBuilder))

print(" id {} - string {}\n".format( id(stringBuilder), stringBuilder))
stringBuilder=''
print(" id {} - string {}\n".format( id(stringBuilder), stringBuilder))

      results in :

id 140226925842928 - string  
 str(): <__main__.StringBuilder object at 0x7f89201a51f0> - repr(): 
 id 140226925842928 - string test

testvaluevaluevaluevaluevaluevaluevaluevaluevaluevalue
 id 140226925842928 - string testvaluevaluevaluevaluevaluevaluevaluevaluevaluevalue

 id 140227461358320 - string

id 140226925842928 - string testvaluevaluevaluevaluevaluevaluevaluevaluevaluevalue
VS
id 140227461358320 - string