remove letters in string python code example

Example 1: 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);
	  	}
	}

Example 2: how to find and remove certain characters from text string in python

a_string = "addbdcd"

a_string = a_string.replace("d", "")

print(a_string)