how to get top 50 sorted key on the basis of its values from a dictionary in python3 code example

Example 1: how can I sort a dictionary in python according to its values?

s = {1: 1, 7: 2, 4: 2, 3: 1, 8: 1}
k = dict(sorted(s.items(),key=lambda x:x[0],reverse = True))
print(k)

Example 2: sort dictionary

#for dictionary d
sorted(d.items(), key=lambda x: x[1]) #for inceasing order
sorted(d.items(), key=lambda x: x[1], reverse=True) # for decreasing order
#it will return list of key value pair tuples