Python3 bytes and hex string conversion

Convert between bytes and hex strings

1. String to bytes

'''
string to bytes
eg:
'0123456789ABCDEF0123456789ABCDEF'
b'0123456789ABCDEF0123456789ABCDEF'
'''
def stringTobytes(str):
    return bytes(str,encoding='utf8')

2.bytes to string

'''
bytes to string
eg:
b'0123456789ABCDEF0123456789ABCDEF'
'0123456789ABCDEF0123456789ABCDEF'
'''
def bytesToString(bs):
    return bytes.decode(bs,encoding='utf8')

3. Hexadecimal string to bytes

'''
hex string to bytes
eg:
'01 23 45 67 89 AB CD EF 01 23 45 67 89 AB CD EF'
b'\x01#Eg\x89\xab\xcd\xef\x01#Eg\x89\xab\xcd\xef'
'''
def hexStringTobytes(str):
    str = str.replace(" ", "")
    return bytes.fromhex(str)
    # return a2b_hex(str)

4.bytes to hexadecimal string

'''
bytes to hex string 
eg:
b'\x01#Eg\x89\xab\xcd\xef\x01#Eg\x89\xab\xcd\xef'
'01 23 45 67 89 AB CD EF 01 23 45 67 89 AB CD EF'
'''
def bytesToHexString(bs):
    # hex_str = ''
    # for item in bs:
    #     hex_str += str(hex(item))[2:].zfill(2).upper() + " "
    # return hex_str
    return ''.join(['%02X ' % b for b in bs])