Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses of length 2*n. code example

Example: Given an integer A pairs of parentheses, write a function to generate all combinations of well-formed parentheses of length 2*A.

# Python3 program to
# Print all combinations
# of balanced parentheses

# Wrapper over _printParenthesis()
def printParenthesis(str, n):
	if(n > 0):
		_printParenthesis(str, 0,
						n, 0, 0);
	return;

def _printParenthesis(str, pos, n,
					open, close):
	
	if(close == n):
		for i in str:
			print(i, end = "");
		print();
		return;
	else:
		if(open > close):
			str[pos] = '}';
			_printParenthesis(str, pos + 1, n,
							open, close + 1);
		if(open < n):
			str[pos] = '{';
			_printParenthesis(str, pos + 1, n,
							open + 1, close);

# Driver Code
n = 3;
str = [""] * 2 * n;
printParenthesis(str, n);