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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def unique_id(length=12, increment=0):
 """ Generate a decent looking alphanumeric unique identifier. First 16 bits are time- incrementing, followed by randomness. This function is used as a nicer looking alternative to: Follows the advice in: https://eager.io/blog/how-long-does-an-id-need-to-be/ Parameters length: int, length of resulting identifier increment: int, number to add to header uint16 useful if calling this function repeatedly in a tight loop executing faster than time can increment the header Returns unique: str, unique alphanumeric identifier """

    # head the identifier with 16 bits of time information
    # this provides locality and reduces collision chances
    head = np.array((increment + time.time() * 10) % 2**16,
                    dtype=np.uint16).tostring()
    # get a bunch of random bytes
    random = np.random.random(int(np.ceil(length / 5))).tostring()
    # encode the time header and random information as base64
    # replace + and / with spaces
    unique = base64.b64encode(head + random,
                              b'  ').decode('utf-8')
    # remove spaces and cut to length
    unique = unique.replace(' ', '')[:length]
    return unique