Python: Bytes, Bytearray

bytesliteral   ::=  bytesprefix(shortbytes | longbytes)
bytesprefix    ::=  "b" | "B" | "br" | "Br" | "bR" | "BR"
shortbytes     ::=  "'" shortbytesitem* "'" | '"' shortbytesitem* '"'
longbytes      ::=  "'''" longbytesitem* "'''" | '"""' longbytesitem* '"""'
shortbytesitem ::=  shortbyteschar | bytesescapeseq
longbytesitem  ::=  longbyteschar | bytesescapeseq
shortbyteschar ::=  <any ASCII character except "\" or newline or the quote>
longbyteschar  ::=  <any ASCII character except "\">
bytesescapeseq ::=  "\" <any ASCII character>

bytes([source[, encoding[, errors]]])

bytearray([source[, encoding[, errors]]])

>>> x = b"Bytes objects are immutable sequences of single bytes"
>>> print(x)
b'Bytes objects are immutable sequences of single bytes'
>>>

#triple single or double quotes allows multiple lines
x = b'''Python Tutorial,
Javascript Tutorial,
MySQL Tutorial'''
print(x)

b'Python Tutorial,\nJavascript Tutorial,\nMySQL Tutorial'

#created from a iterable of ints, string, bytes or buffer objects.
x = bytes('Python, bytes', 'utf8')
print(x)

b'Python, bytes'

#create a bytes object
x = b'El ni\xc3\xb1o come camar\xc3\xb3n'
print(x)

b'El ni\xc3\xb1o come camar\xc3\xb3n' 

# create a string using the decode() method of bytes. 
#This method takes an encoding argument, such as UTF-8, and optionally an errors argument.
x = b'El ni\xc3\xb1o come camar\xc3\xb3n'
s = x.decode()
print(type(s))
print(s)

El niño come camarón

#create a bytes object encoded using 'cp855'
x = b'\xd8\xe1\xb7\xeb\xa8\xe5 \xd2\xb7\xe1'
print(x)
#return a string using decode 'cp855'
y = x.decode('cp855')
print(y)

b'\xd8\xe1\xb7\xeb\xa8\xe5 \xd2\xb7\xe1'
привет мир

#create a string with hexadecimal data
x = '45678c6c56f205876f72c64'
print(x)

45678c6c56f205876f72c64

#this class method returns a bytes object, decoding the given string object.
#the string must contain two hexadecimal digits per byte.
x = '45678c6c56f205876f72c64'
y = bytes.fromhex(x)

b'.\xf0\xf1\xf2'

#return an integer representing the Unicode code point of that character.
x = ord(b'm')
print(x)

109

#create a bytes object
y = b'Python bytes'
#generates a list of codes from the characters of bytes
z = list(y)
print(z)

[80, 121, 116, 104, 111, 110, 32, 98, 121, 116, 101, 115]

#create a str
x = b'Python mapping table characters'
print(x)

b'Python mapping table characters' 

b_table = bytes.maketrans(b'abcdef', b'uvwxyz')
print(type(b_table))
print(b_table)

<class 'bytes'>  
b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !"#$%  
&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`uvwxyzghijklmnopqrstuvwxyz{|}~\x7f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x  
90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\  
xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3  
\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\xf4\xf  
5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff'

b_table = bytes.maketrans(b'abcdef', b'uvwxyz')
str = 'Write a Python function to find a distinct pair of numbers whose product is odd from a sequence of integer values.'
b_new = str.translate(b_table)
print(b_new)

Writy u Python zunwtion to zinx u xistinwt puir oz numvyrs whosy proxuwt is oxx zrom u syquynwy oz intygyr vuluys.

>>> import binascii
>>> binascii.hexlify("Python".encode("utf8"))
b'507974686f6e'
>>> binascii.unhexlify(_).decode("utf8")
'Python'
>>> 

>>> #this method return a single character based on the integer value.
>>> x = chr(60)
>>> print(x)
<
>>> x = chr(50)
>>> print(x)
2
>>> #create a list with integers in the range 0 through 255
>>> y = [70, 111, 106, 94, 101, 100, 22, 95, 105, 22, 91, 87, 125, 135]
>>> print(y)
[70, 111, 106, 94, 101, 100, 22, 95, 105, 22, 91, 87, 125, 135]
>>> #create a bytes object from a list of integers in the range 0 through 255.
>>> z = bytes(y)
>>> print(z)
b'Foj^ed\x16_i\x16[W}\x87'
>>> 

>>> #create a string
>>> x = "Python, Bytes"
>>> print(x)
Python, Bytes
>>> #know the length of the string using the len() function
>>> print(len(x))
13
>>> #create a bytes object
>>> y = bytes(x, "utf8")
>>> print(y)
b'Python, Bytes'
>>> #know the length of the bytes object using the len() function
>>> print(len(y))
13
>>> 

>>> #create a bytes object
>>> x = b"byte 213"
>>> print(x)
b'byte 213'
>>> #The * operator allow repeat the characters of a bytes object
>>> print(x * 5)
b'byte 213byte 213byte 213byte 213byte 213'
>>> #create two bytes objects.
>>> x1 = bytes([70, 111, 106, 94, 101, 100, 22, 95, 105, 22, 91, 87, 125, 135])
>>> x2 = b"Python"
>>> #The + operator allow create a new bytes object joining two or more bytes.
>>> x = x1 + x2
>>> print(x)
b'Foj^ed\x16_i\x16[W}\x87Python'
>>> #create a bytes object combining operators
>>> x = b"Python" + b"Bytes" * 3 + b"$"
>>> print(x)
b'PythonBytesBytesBytes$'
>>> 

>>> y = [80, 121, 116, 104, 111, 110, 32, 105, 115, 32, 101, 97, 115, 121]
>>> print(y)
[80, 121, 116, 104, 111, 110, 32, 105, 115, 32, 101, 97, 115, 121]
>>> #create a bytes object
>>> x1 = bytes([70, 111, 106, 94, 101, 100, 22, 95, 105, 22, 91, 87, 125, 135])
>>> print(x1)
b'Foj^ed\x16_i\x16[W}\x87'
>>> #is similar to the handling of lists, the index is defined in brackets
>>> x = y[3]
>>> print(x)
104
>>> print(chr(x))
h
>>> #can also use negative indices to get a byte from bytes object
>>> x = [-8]
>>> print(x)
[-8]
>>> x = y[-8]
>>> print(x)
110
>>> print(chr(x))
n
>>> 

>>> #create a bytearray from a bytes object
>>> x = bytearray(b"Python Bytes")
>>> print(x)
bytearray(b'Python Bytes')
>>> #create a bytearray from a string defining the standard of coding
>>> x = bytearray("Python Bytes", "utf8")
>>> print(x)
bytearray(b'Python Bytes')
>>> #create a bytearray from a list of integers in the range 0 through 255
>>> x = bytearray([94, 91, 101, 125, 111, 35, 120, 101, 115, 101, 200])
>>> print(x)
bytearray(b'^[e}o#xese\xc8')
>>> 

>>> #bytearray objects are a mutable counterpart to bytes objects
>>> x = bytearray("Python bytearray", "utf8")
>>> print(x)
bytearray(b'Python bytearray')
>>> #can remove items from the bytes
>>> del x[11:15]
>>> print(x)
bytearray(b'Python bytey')
>>> #can add items from the bytes
>>> x[11:15] = b" object"
>>> print(x)
bytearray(b'Python byte object')
>>> #can use the methods of mutable type iterable objects as the lists
>>> x.append(45)
>>> print(x)
bytearray(b'Python byte object-')
>>> 

>>> #create a bytes object from a list of integers in the range 0 through 255
>>> x = bytes([105, 100, 107, 112, 132, 118, 107, 112, 200])
>>> print(x)
b'idkp\x84vkp\xc8'
>>> #generates a new array of bytes from a bytes object
>>> x1 = bytearray(x)
>>> print(x1)
bytearray(b'idkp\x84vkp\xc8')
>>> 

>>> #create a bytes object
>>> x = b"Python slice"
>>> print(x)
b'Python slice'
>>> #b[start:stop] the start index is inclusive and the end index is exclusive.
>>> x1 = x[2:6]
>>> print(x1)
b'thon'
>>> #if the start index isn't defined, is starts from the beginning
>>> x1 = x[-5:]
>>> print(x1)
b'slice'
>>> #if the end index isn't defined, it goes until the end
>>> x1 = x[:4]
>>> print(x1)
b'Pyth'
>>> #if neither is defined, returns the full bytes object
>>> x1 = x[:]
>>> print(x1)
b'Python slice'
>>> 

>>> # bytes objects are immutable sequences of integers, each value in the sequence
>>> # string objects are immutable sequences of unicode characters.
>>> x = "Python String"
>>> y = b"Python String"
>>> print(x)
Python String
>>> print(y)
b'Python String'
>>> # Found in unicode representation of characters but not in ascii
>>> x = "Python"
>>> y = bytes("Python", "utf8")
>>> print(x)
Python
>>> print(y)
b'Python'
>>>