In this homework you will complete parts of the UPGMA program that
we are working on in class. 

Part I

Write a Python program that takes a matrix file as input and
stores it in a two dimensional matrix D. For example if the 
input file contains

0  10 2 3 
10 0  3 4
2  3  0 5 
3  4  5 0

then your program should create the two dimensional matrix D 

[ [0, 10, 2, 3],
  [10, 0, 3, 4],
  [2, 3, 0, 5],
  [3, 4, 5, 0] ]

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Part II

To the above program add a part that creates another two dimensional
matrix d. If the matrix in the input has dimension n by n then d would
have dimensions 2n-1. The first n rows and columns of d are the same as
D and remaining entries contain the character 'x'.

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Part III

Add code to the above to initialize the P, L, R, and leaves matrices 
for the input in matrix.txt. Remember to initialize all values to -1. 

Remember that your solution must work for a matrix of any dimension
and not just the four by four given in the example.

Submit a hardcopy on April 4th in class.