delete letter in string python code example

Example 1: take off character in python string

s = 'abc12321cba'

print(s.replace('a', ''))

Example 2: remove from string python

"Str*ing With Chars I! don't want".replace('!','').replace('*','')

Example 3: how to remove letters from string

public extractLetters(String str){
	String result="";
	for(int i= 0; i< str.length; i++){
	    if(Character.isLetter(str.charAt(i))){
	    result+=str.charAt(i);
	  	}
	}