A palindrome is a word, phrase, number, or other sequence of characters which reads the same backward as forward. Examples of numerical palindromes are: 
2332
110011
54322345
For this kata, single digit numbers will not be considered numerical palindromes. 
For a given number ```num```, write a function to test if the number contains a numerical palindrome or not and return a boolean (true if it does and false if does not). Return "Not valid" if the input is not an integer or is less than 0. 
Note: Palindromes should be found without permutating ```num```. 
```
palindrome(5) => false
palindrome(1221) => true
palindrome(141221001) => true
palindrome(1215) => true 
palindrome(1294) => false 
palindrome("109982") => "Not valid"
```
def palindrome(n):
    return 'Not valid' if type(n) != int or n < 0 else any(s == s[::-1] for s in subs(str(n)))
        
def subs(s):
    return [s[i:i+j] for j in range(2, len(s)+1) for i in range(len(s)-j+1)]
def palindrome(n):
    return 'Not valid' if type(n) != int or n < 0 else any(s == s[::-1] for s in subs(str(n)))
        
def subs(s):
    return [s[i:i+j] for j in range(2, len(s)+1) for i in range(len(s)-j+1)]