#Used built-in StringTools package
is_pangram := proc(str)
	local present := StringTools:-LowerCase~(select(StringTools:-HasAlpha, StringTools:-Explode(str)));
	local alphabets := {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
	present := convert(present, set);
	return evalb(present = alphabets);
end proc;