Chapter 02: Python ‘str’ Questions And Answer (Without Code)

Q: What is a string in Python? A: In Python, a string is a sequence of characters enclosed within single, double, or triple quotes.

Q: How do you create a multi-line string in Python? A: Multi-line strings can be created by using triple quotes, either ''' or """.

Q: How can you concatenate two strings in Python? A: You can concatenate strings using the + operator.

Q: How do you find the length of a string? A: You can find the length of a string using the len() function.

Q: Can you change a string in place in Python? A: No, strings in Python are immutable, which means you cannot change them in place after they are created.

Q: How do you access the character at the nth position of a string? A: You can access it using indexing, like string[n].

Q: How do you slice a substring from a string? A: You can slice a substring using the syntax string[start:stop:step].

Q: How do you convert a number to a string? A: You can convert a number to a string using the str() function.

Q: How do you make a string uppercase? A: You use the .upper() method, like string.upper().

Q: How can you check if a string contains a particular substring? A: You can check using the in keyword, like 'substring' in string.

Q: How do you replace parts of a string with a different text? A: You can replace parts of a string using the .replace() method, like string.replace('old', 'new').

Q: How do you check if a string starts with a specific substring? A: You can check if a string starts with a specific substring using the .startswith() method.

Q: How do you check if a string is all uppercase? A: You can check if all characters in a string are uppercase using the .isupper() method.

Q: How do you split a string into a list of substrings? A: You can split a string into a list of substrings using the .split() method.

Q: How do you join a list of strings into a single string? A: You can join a list of strings into a single string using the .join() method, like 'separator'.join(list_of_strings).

Q: How do you format a string with variables in Python? A: You can format a string with variables using formatted string literals (f-strings), like f'Hello {name}!'.

Q: How do you strip whitespace from the beginning and end of a string? A: You can strip whitespace using the .strip() method.

Q: How do you find the index of a substring in a string? A: You can find the index of the first occurrence of a substring using the .find() method.

Q: How do you convert a string to a list of characters? A: You can convert a string to a list of characters by using list(string).

Q: How do you check if all characters in a string are alphanumeric? A: You can check if all characters are alphanumeric using the .isalnum() method.

Q: How do you convert all characters in a string to lowercase? A: You can convert all characters to lowercase using the .lower() method.

Q: How do you reverse a string in Python? A: You can reverse a string by using slicing, like string[::-1].

Q: How do you check if a string contains only digits? A: You can check if a string contains only digits using the .isdigit() method.

Q: How do you check if a string ends with a specific substring? A: You can check if a string ends with a specific substring using the .endswith() method.

Q: How do you capitalize the first character of a string? A: You can capitalize the first character of a string using the .capitalize() method.

Q: How do you count the occurrences of a specific character in a string? A: You can count the occurrences of a character using the .count() method.

Q: How do you remove a specific character from the beginning and end of a string? A: You can remove a specific character using the .strip() method with the character as an argument.

Q: How do you check if a string is alphanumeric? A: You can check if a string is alphanumeric using the .isalnum() method.

Q: How do you check if a string is a valid identifier? A: You can check if a string is a valid identifier using the .isidentifier() method.

Q: How do you find the lowest index of a substring in a string? A: You can find the lowest index of a substring using the .find() method.

Q: How do you check if a string contains only letters? A: You can check if a string contains only letters using the .isalpha() method.

Q: How do you convert the first character of each word to uppercase in a string? A: You can convert the first character of each word to uppercase using the .title() method.

Q: How do you check if a string contains only whitespace characters? A: You can check if a string contains only whitespace characters using the .isspace() method.

Q: How do you check if a string is in title case? A: You can check if a string is in title case using the .istitle() method.

Q: How do you left-align a string within a certain width? A: You can left-align a string using the .ljust() method with the width as an argument.

Q: How do you center a string within a certain width? A: You can center a string using the .center() method with the width as an argument.

Q: How do you right-align a string within a certain width? A: You can right-align a string using the .rjust() method with the width as an argument.

Q: How do you check if all characters in a string are in lowercase? A: You can check if all characters are in lowercase using the .islower() method.

Q: How do you replace characters in a string using a translation table? A: You can replace characters using the .translate() method with a translation table as an argument.

Q: How do you remove a specific character from the right end of a string? A: You can remove a specific character from the right end using the .rstrip() method with the character as an argument.

Q: How do you convert a string to its numerical representation, such as from ‘123’ to 123? A: You can convert a string to an integer using the int() function, or to a float using the float() function, depending on the format of the number.

Q: How do you check if a string is a valid Python keyword? A: You can check if a string is a valid Python keyword using the keyword module with keyword.iskeyword(string).

Q: How do you encode a string to bytes in Python? A: You can encode a string to bytes using the .encode() method, specifying the encoding type, like string.encode('utf-8').

Q: How do you format a string by inserting values into placeholders? A: You can insert values into a string’s placeholders using the .format() method, like 'Hello, {}'.format(name).

Q: How do you concatenate a string and a number in Python? A: To concatenate a string and a number, you must first convert the number to a string using the str() function.

Q: How do you find out the character corresponding to an integer using the ASCII table? A: You can find the character corresponding to an integer using the chr() function.

Q: How do you find the integer corresponding to a character using the ASCII table? A: You can find the integer corresponding to a character using the ord() function.

Q: How do you remove a specific character from the left end of a string? A: You can remove a specific character from the left end using the .lstrip() method with the character as an argument.

Q: How do you check if all characters in a string are printable? A: You can check if all characters in a string are printable using the .isprintable() method.

Q: How do you repeat a string a certain number of times? A: You can repeat a string by using the multiplication operator, like 'string' * n.

Q: How do you check if a string is composed only of numeric characters? A: You can check if a string has only numeric characters using the .isnumeric() method.

Q: How do you check if a string is a valid variable name in Python? A: You can check if a string is a valid variable name using the .isidentifier() method.

Q: How do you convert a list of strings into a single string with each element separated by a newline? A: You can join a list of strings into a single string separated by newlines using '\n'.join(list_of_strings).

Q: How do you check if a string is composed of decimal characters? A: You can check if a string is composed of decimal characters using the .isdecimal() method.

Q: How do you check if a string follows the case of a title, with the first letter of each word capitalized? A: You can check if a string is in title case using the .istitle() method.

Q: How do you find the maximum alphabetical character in a string? A: You can find the maximum alphabetical character using the max(string) function.

Q: How do you find the minimum alphabetical character in a string? A: You can find the minimum alphabetical character using the min(string) function.

Q: How do you create a string from a list of characters? A: You can create a string from a list of characters by using ''.join(list_of_characters).

Q: How do you swap the case of each letter in a string? A: You can swap the case of each letter using the .swapcase() method.

Q: How do you pad a string with zeros on the left to fill a certain width? A: You can pad a string with zeros on the left using the .zfill() method with the width as an argument.