How to use backslash on double quote

Question

print('I\'m learning Python!')
print("A number enclosed in double quotes: "42"")

Answer 1

The backslash escape characters with special meanings. n becomes a newline \n, and quotes becomes a character without the ‘end the string’ meaning the quote normal gets inside a string, if the string began with the same kind of quote. So it becomes an ordinary character with a backslash \" .

s0 = "\"" becomes a string with one character:
len(s0) = 1 and
print(s0) gives: "

There is nothing special with “ (duoble qoute) comparing to ‘ (singel quote).

So to enclose a number in quotes you can escape them:
s1 = "\"42\""
or:
s2 = '"42"'

In the last one the string starts and ends with single qutoes, so the double quotes becomes ordinary characters inside the string.

Answer 2

This line doesn't produce errors. It is okay as it is:
print('I\'m learning Python!')

This line was producing an error.
print("A number enclosed in double quotes: "42"")

The corrected syntax is as follows:
print("A number enclosed in double quotes: \"42\"")