def lucky_sevens(*numbers)
istrue = false
sum = 0
i = 0
while i < numbers.length
num = numbers[i]
sum = num + sum
i += 1
end
if sum == 7
istrue = true
end
return istrue
end

puts lucky_sevens(1,2,3,12)
puts lucky_sevens(1,2,3,1)
puts lucky_sevens(1,2,3,1,2,2,1,7,4,7,0,7,321,)