added exercises for list comprehensions

list_comprehensions/solution/comprehensions.py

@@ -0,0 +1,41 @@
+def divisible_by_7(n: int) -> list[int]:
+    """
+    Returns a list of all numbers till 'n' that are divisible by '7'
+    """
+    return [x for x in range(1, n) if x % 7 == 0]
+
+
+def contains_3(n: int) -> list[int]:
+    """
+    Returns a list of all numbers that contain the digit '3' in them
+    """
+    return [x for x in range(1, n) if '3' in str(x)]
+
+
+def count_spaces(string: str) -> int:
+    """
+    Count the spaces in a string
+    """
+    return len([ch for ch in string if ' ' == ch])
+
+
+def remove_vowels(string: str) -> str:
+    """
+    Remove all vowels from the string
+    """
+    return ''.join([ch for ch in string if ch.lower() not in 'aeiou'])
+
+
+def word_lengths(string: str) -> dict[str, int]:
+    """
+    Create a dictionary of all words with their lengths
+    """
+    return {word: len(word) for word in string.split(' ') if len(word) > 0}
+
+
+def prime_numbers(n: int) -> list[int]:
+    """
+    Returns a list of all prime numbers till 'n' (HARD)
+    """
+    return [x for x in range(2, n) if all(x % y != 0 for y in range(2, x))]
+