Nick Ku- Bit Encoder and Decoder

"""bitencoder and bitdecoder by Nick Ku"""

def number_to_character( number ):
    if number < 10:
        return chr( number + 48)
    elif 10 <= number <= 35:
        return chr( number + 55 )
    elif 35 < number <= 61:
        return chr( number + 61 )
    elif number == 62:
        return chr( 45 )
    elif number == 63:
        return chr( 43 )
    else:
        print ('Invalid number')

def character_to_number( character ):
    number = ord( character )
    if 48 <= number <= 57:
        return number-48
    elif 65 <= number <= 90:
        return number - 55
    elif 97 <= number <= 122:
        return number - 61
    elif number == 45:
        return 62
    elif number == 43:
        return 63
    else:
        print ('Invalid character')

def encode( number ):
    new_number = ""
    if number < 0:
        print ('Negative numbers are invalid')
    while number !=0:
        remainder = number % 64
        new_number += number_to_character(remainder)
        number //= 64
    while len(new_number) < 6:
        new_number += '0'
    new_number = new_number[:6]
    return new_number

def decode( number ):
    result = 0
    exponent = 0
    for item in number:
        result += character_to_number(item) * (64**exponent)
        exponent += 1
    return result

def bitencode( number, bits = [ 5, 11, 17, 23, 29, 35, 4, 10, 16, 22, 28, 34, 3,  9, 15, 21, 27, 33, 2,
    8, 14, 20, 26, 32, 1,  7, 13, 19, 25, 31, 0,  6, 12, 18, 24, 30,]):
    bit_shift = bits[::-1]
    new_number = 0
    order = 0
    for x in bit_shift:
        new_number += (((number >> x) & 1) << order)
        order +=1
    return encode(new_number)

def bitdecode( number, bits = [ 5, 11, 17, 23, 29, 35, 4, 10, 16, 22, 28, 34, 3,  9, 15, 21, 27, 33, 2,
    8, 14, 20, 26, 32, 1,  7, 13, 19, 25, 31, 0,  6, 12, 18, 24, 30,]):
    bit_shift = bits[::-1]
    new_number = 0
    old_number = decode(number)
    order = 0
    for x in bit_shift:
        new_number += (((old_number >> order) & 1) << x)
        order += 1
    return new_number