Solve using python(if you can explain your steps cause i really wanna understand that would be awesome)

Write a function, called constrainedMatchPair which takes three arguments: a tuple representing starting points for the first substring, a tuple representing starting points for the second

substring, and the length of the first substring. The function should return a tuple of all members (call it n) of the first tuple for which there is an element in the second tuple (call it k) such that n+m+1 = k, where m is the length of the first substring. Complete the definition

def constrainedMatchPair(firstMatch,secondMatch,length):