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Error

Given an integer N and an array of N integers. Calculate the sum of products of all pairs of integers of the array.

Note: Since the answer can be large, return the answer modulo 10^{9}+7.

**Example 1:**

**Input:**
N=3
A=[1,2,3]
**Output:**
11
**Explanation:**
1x2+2x3+1x3=11
So, the answer is 11.

**Example 2:**

**Input:**
N=3
A=[2,2,3]
**Output:**
16
**Explanation:**
2x2+2x3+3x2=16.
So, the answer is 16.

**Your Task:**

You don't need to read input or print anything. Your task is to complete the function **productOfPairs()** which takes the integer N and array A as input parameters and returns the sum of the product of all pairs of integers from the array.

**Expected Time Complexity:**O(N)

**Expected Auxillary Space:**O(1)

**Constraints:**

1<=N,A[i]<=10^{6}

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Sum of product of all pairs

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