The **variance** of a string is defined as the largest difference between the number of occurrences of **any** `2` characters present in the string. Note the two characters may or may not be the same.

Given a string `s` consisting of lowercase English letters only, return _the **largest variance** possible among all **substrings** of_ `s`.

A **substring** is a contiguous sequence of characters within a string.

**Example 1:**

**Input:** s =  "aababbb "
**Output:** 3
**Explanation:**
All possible variances along with their respective substrings are listed below:
- Variance 0 for substrings  "a ",  "aa ",  "ab ",  "abab ",  "aababb ",  "ba ",  "b ",  "bb ", and  "bbb ".
- Variance 1 for substrings  "aab ",  "aba ",  "abb ",  "aabab ",  "ababb ",  "aababbb ", and  "bab ".
- Variance 2 for substrings  "aaba ",  "ababbb ",  "abbb ", and  "babb ".
- Variance 3 for substring  "babbb ".
Since the largest possible variance is 3, we return it.

**Example 2:**

**Input:** s =  "abcde "
**Output:** 0
**Explanation:**
No letter occurs more than once in s, so the variance of every substring is 0.

**Constraints:**

*   `1 <= s.length <= 104`
*   `s` consists of lowercase English letters.


def maximum_good_people(statements):
    n = len(statements)
    count_good = 0
    for i in range(n):
        is_good = True
        for j in range(n):
            if statements[j][i] == 1 and statements[i][j] == 0:
                is_good = False
                break
        if is_good:
            count_good += 1
    return count_good
