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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def submatrix(matrix,i1,i2,j1,j2):
 """ returns the submatrix defined by the index bounds i1-i2 and j1-j2 Endpoints included! """


    new = []
    for i in range(i1,i2+1):
        new.append(matrix[i][j1:j2+1])
    return _n.array(new)