bytes() method in Python is used to create a sequence of bytes. In this article, we will check How bytes() methods works in Python.

a = "geeks"

 # UTF-8 encoding is used
b = bytes(a, 'utf-8') 
print(b)

b'geeks'

Syntax of bytes()

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

Parameters:

source (optional)

• A string will be encoded into bytes using the specified encoding (default is 'utf-8').
• An iterable will have each element converted into bytes but it must have integers between 0 and 255.
• An integer creates a bytes object of that size with all elements initialized to 0.

encoding (optional)

This parameter is used when the source is a string. It specifies the encoding format to convert the string into bytes. The default encoding is 'utf-8' but you can use other encodings like 'ascii', 'utf-16', etc.

errors (optional)

Defines how to handle errors during the encoding process.

• 'strict': Raises a UnicodeEncodeError if there is an error.
• 'ignore': Ignores characters that can't be encoded.
• 'replace': Replaces characters that can't be encoded with a placeholder (usually a question mark).

Return Type:  

• return type of the bytes() method is a bytes object. A bytes object is an immutable sequence of integers in the range from 0 to 255.

Using Custom Encoding

If the string contains characters from other languages, we can specify a different encoding:

a = "गीक्स"
b = bytes(a, 'utf-16')  

# Converts the string to bytes using UTF-16 encoding
print(b)

b'\xff\xfe\x17\t@\t\x15\tM\t8\t'

Convert String to Bytes

Python String to bytes using the bytes() function, for this we take a variable with string and pass it into the bytes() function with UTF-8 parameters. When we pass a string to the bytes() method, we also need to tell Python which "language" (encoding) to use to convert the string.

s = "Welcome to Geeksforgeeks"

b = bytes(s, 'utf-8')

print(b)

b'Welcome to Geeksforgeeks'

Converting a List of Integers to Bytes

Each number in the list must be between 0 and 255 because each byte can only hold numbers in that range. When we pass a list of numbers to the bytes() method, Python will create a bytes object where each number in the list corresponds to one byte.

a = [215, 66, 67]  

 # Converts the list of integers into bytes
b = bytes(a) 
print(b)

b'\xd7BC'

Creating a Bytes Object with a Specific Size

By passing a single integer to bytes(), Python will create a bytes object of that length, filled with zero values (because a byte is initially 0).

a = 5  

# Creates a bytes object of length 5, with all zero values
b = bytes(a)  
print(b)

b'\x00\x00\x00\x00\x00'