def appendAtBeginningFront(x, L):
	return [x + element for element in L]

def bitStrings(n):
	if n == 0:
		return []
	if n == 1:
		return ['0', '1']
	else:
		return (appendAtBeginningFront('0', bitStrings(n-1)) + appendAtBeginningFront('1', bitStrings(n-1)))

print(bitStrings(3))


def bitStrings(n):
	if n == 0:
		return []
	if n == 1:
		return ['0', '1']
	return [digit + bitstring for digit in bitStrings(1) for bitstring in bitStrings(n-1)]

print(bitStrings(3))
171de79c0677a6264102116276959ccde0667641
<mask token>


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    return [(digit + bitstring) for digit in bitStrings(1) for bitstring in
        bitStrings(n - 1)]


<mask token>

def appendAtBeginningFront(x, L):
    return [(x + element) for element in L]


<mask token>


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    return [(digit + bitstring) for digit in bitStrings(1) for bitstring in
        bitStrings(n - 1)]


<mask token>

def appendAtBeginningFront(x, L):
    return [(x + element) for element in L]


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    else:
        return appendAtBeginningFront('0', bitStrings(n - 1)
            ) + appendAtBeginningFront('1', bitStrings(n - 1))


<mask token>


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    return [(digit + bitstring) for digit in bitStrings(1) for bitstring in
        bitStrings(n - 1)]


<mask token>

def appendAtBeginningFront(x, L):
    return [(x + element) for element in L]


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    else:
        return appendAtBeginningFront('0', bitStrings(n - 1)
            ) + appendAtBeginningFront('1', bitStrings(n - 1))


print(bitStrings(3))


def bitStrings(n):
    if n == 0:
        return []
    if n == 1:
        return ['0', '1']
    return [(digit + bitstring) for digit in bitStrings(1) for bitstring in
        bitStrings(n - 1)]


print(bitStrings(3))

def appendAtBeginningFront(x, L):
	return [x + element for element in L]

def bitStrings(n):
	if n == 0:
		return []
	if n == 1:
		return ['0', '1']
	else:
		return (appendAtBeginningFront('0', bitStrings(n-1)) + appendAtBeginningFront('1', bitStrings(n-1)))

print(bitStrings(3))


def bitStrings(n):
	if n == 0:
		return []
	if n == 1:
		return ['0', '1']
	return [digit + bitstring for digit in bitStrings(1) for bitstring in bitStrings(n-1)]

print(bitStrings(3))