Count Good Meal_s

class Solution:
    def countPairs(self, deliciousness: List[int]) -> int:
        mod=10**9 +7 
        # Getting a count of all foods in a given 
        foods_frequency=Counter(deliciousness)
        
        # Finding maximum value we have in the given
        maximum_number=max(deliciousness)
        
        # Finding Maximum power for two we will have from given array
        maximum_2_power= int(log2(maximum_number)) + 1
        
        answer=0
        for current_food in foods_frequency:
        
            for current_power in range(maximum_2_power+1):
                # Find the difference of the current number with 2 power numbers 
                difference = (2**(current_power)) -current_food
                
                if difference in foods_frequency and foods_frequency[difference]: 
                    current_food_freq=foods_frequency[current_food]
                    
                    if difference==current_food:
                        # taking Combination by selecting two element 
                        # at once C(n,2) = (n*(n-1))//2
                        combination=(current_food_freq*(current_food_freq-1))//2 
                        answer += combination
                        
                    else:
                        diffent_food_freq=foods_frequency[difference]
                        answer+=(current_food_freq*diffent_food_freq)
                        
            foods_frequency[current_food]=0
        return answer%mod