1 Python Strings

Question 1

How can I convert all my text to lowercase?

Answer 1

text = “NLP is POWERFUL!”
print(text.lower())

Output:”nlp is powerful!”

Question 2

My sentence has unwanted spaces at the beginning or end. How do I clear them?

Answer 2

text = “ clean me “
print(text.strip())

Output:
“clean me”

Question 3

I want to remove commas or change emojis to words.

Answer 3

text = “I love NLP, AI, and ML 💡”
cleaned = text.replace(“,”, “”).replace(“💡”, “[idea]”)
print(cleaned)

Output:
“I love NLP AI and ML [idea]”

Question 4

How do I break my sentence into words?

Answer 4

text = “I love machine learning”
words = text.split()
print(words)

Output:
[‘I’, ‘love’, ‘machine’, ‘learning’]

Question 5

I cleaned my words. How do I put them back into a sentence?

Answer 5

words = [‘nlp’, ‘is’, ‘awesome’]
sentence = “ “.join(words)
print(sentence)

Output:
“nlp is awesome”

Question 6

I want to know where a word starts in a sentence.

Answer 6

text = “Python is everywhere”
print(text.find(“is”)) # Returns index
print(text.index(“Python”)) # Returns 0

Output:
7
0

Question 7

I want to know how many times a word or letter appears.

Answer 7

text = “data data data science”
print(text.count(“data”))

Output:
3

Question 8

I want to grab the first 5 characters or last 3 letters.

Answer 8

text = “language”
print(text[:5]) # First 5: “langu”
print(text[-3:]) # Last 3: “age”

Question 9

How do I check if my sentence starts or ends with something?

Answer 9

text = “Natural Language Processing”
print(text.startswith(“Natural”))
print(text.endswith(“Processing”))

Output:
True
True

Question 10

I want to check if a string is just letters, numbers, both, or only space.

Answer 10

print(“AI”.isalpha()) # True
print(“2024”.isdigit()) # True
print(“AI2024”.isalnum()) # True
print(“ “.isspace()) # True

Question 11

How many characters are in my string?

Answer 11

text = “hello”
print(len(text))

Output: 5

Question 12

zfill(width)

Answer 12

id = “7”
print(id.zfill(4))

Output: “0007”