def count_keys(n):
    "Generate outcome bitstrings for n-qubits.\n\n    Args:\n        n (int): the number of qubits.\n\n    Returns:\n        list: A list of bitstrings ordered as follows:\n        Example: n=2 returns ['00', '01', '10', '11'].\n    "
    return [bin(j)[2:].zfill(n) for j in range((2 ** n))]
Generate outcome bitstrings for n-qubits.

Args:
    n (int): the number of qubits.

Returns:
    list: A list of bitstrings ordered as follows:
    Example: n=2 returns ['00', '01', '10', '11'].
def count_keys(n):
    "Generate outcome bitstrings for n-qubits.\n\n    Args:\n        n (int): the number of qubits.\n\n    Returns:\n        list: A list of bitstrings ordered as follows:\n        Example: n=2 returns ['00', '01', '10', '11'].\n    "
    return [bin(j)[2:].zfill(n) for j in range((2 ** n))]