Check string is a number
The mission is in Blocked Mode.
Access to the solutions is blocked for a day or two (even after you share your own), until we'll have enough solutions for you to check.
All users who've solved the mission will get the notifications about their opening.
Check string is number
Input: String of values.
Output: Bool.
Examples:
assert is_number("678") == True
assert is_number("hi") == False