How do you add special characters in python?

I am making a set in Python to house all the symbols on my keyboard, but obviously a few pose some issues. Is there a way to get them all in there without encountering problems?

Here is my set:

symbols = {`,~,!,@,#,$,%,^,&,*,(,),_,-,+,=,{,[,},},|,\,:,;,",',<,,,>,.,?,/}

To get around commenting out most of it, since in Python # is to comment, I enclosed everything like so:

symbols = {'`','~','!','@','#','$','%','^','&','*','(',')','_','-','+','=','{','[','}','}','|','\',':',';','"',''','<',',','>','.','?','/'}

Which works for that character, but now I can already see an issue when I come across the ' and \. Is there a better way to make this set?

Escape Characters

To insert characters that are illegal in a string, use an escape character.

An escape character is a backslash \ followed by the character you want to insert.

An example of an illegal character is a double quote inside a string that is surrounded by double quotes:

Example

You will get an error if you use double quotes inside a string that is surrounded by double quotes:

txt = "We are the so-called "Vikings" from the north."

Try it Yourself »

To fix this problem, use the escape character \":

Example

The escape character allows you to use double quotes when you normally would not be allowed:

txt = "We are the so-called \"Vikings\" from the north."

Try it Yourself »

Other escape characters used in Python:

The characters which have some unique functionality, such characters are called special characters.

List of Python special/escape characters:

• \n - Newline
• \t- Horizontal tab
• \r- Carriage return
• \b- Backspace
• \f- Form feed
• \'- Single Quote
• \"- double quote
• \\-Backslash
• \v -vertical tab
• \N - N is the number for Unicode character
• \NNN - NNN is digits for Octal value
• \xNN - NN is a hex value; \x is used to denote following is a hex value.
• \a - bell sound, actually default chime

>>> print("chercher\ntech")
chercher
tech
>>> print("chercher\ttech")
chercher        tech
>>> print("This is\" symbol")
This is" symbol
>>> print('This is \' symbol')
This is ' symbol
>>> print("This is\\  symbol")
This is\  symbol
>>> print("Chercher\rTech")
Techcher
>>> print("CherCher\bTech")
CherCheTech
>>> print("CherCher\fTech")
CherCher♀Tech
>>> print("\110\151")
Hi
>>> print("\x48\x69")
Hi
>>>

How to check if a string contains any special characters

Import the re to match the string using regular expression.

The search function matches each character present inside the test_string string with the special characters present in the regular expression.

If there is a match it returns the character that matched otherwise it returns None. Based on the result, structure your logic.

import re
string_check= re.compile('[@_!#$%^&*()<>?/\|}{~:]')
test_string = "[email protected]"
 
if(string_check.search(test_string) == None):
    print("Contains NO Special Characters.") 
else: 
    print("Contains Special Characters.")
    print(string_check.search(test_string)) #print the special chars

Output

Contains Special Characters.

You can check whether a string starts with a special character.

test_string = "[email protected]$tech"
print(test_string.startswith("$"))
#Output
True

How to print special characters in Python

Sometimes we might want to print the special characters to see special characters present in the string. For example, printing special characters in normal way prints the Str\ting as Str ing because we have "\t" in the string.

To print the special characters as it is, we have to use repr() functions.

base_string = "Str\ting"
special_string = repr(base_string)
print("base string: "+ base_string)
print("special_string :"+special_string)

The output of printing special characters

base string: Str	ing
special_string :'Str\ting'

Python Abstract Method and Abstract Class

Python comments are those who start with the hash(#) character and extended to the end of the physical line, where the python virtual machine does not execute the line with the hash character, A comment may appear at the start of the line or following by the whitespace but never come in between the string.

For multiline comments, you can use the hash character at the beginning of every line.

# print("chercher.tech software solutions")
print("This is an example of comment in python")

So if you observe, in the above image, the line with the hash character has not printed in the output as it is ignored by the python virtual machine.

Another way to comment on multiple lines in python is by using triple quotes. The string literal when not assigned to a variable is completely ignored by the python interpreter. Three consecutive single ''' or double " " " quotes can be placed before and after the text for long comments in the code.

Example,

''' 
   This is a multiple
   line comment in python  '''

" " " The comments are completely
     ignored by python interpreter " " "

Python Mutability

In Python, the constants are usually declared and assigned on a module, and a module means the new file containing a variable and functions which is imported to the main file.

Constants are written in uppercase and separated by the underscore, and this constant concept is not really implemented in python.

MAX-VALUE=10
MAX-VALUE=20

How do you insert a special character in Python?

How do you add a special character to a string in Python?

How do you print special symbols in Python?

How do you write symbols in Python?