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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 calculate_tetra_zscores(infilenames):
 """Returns dictionary of TETRA Z-scores for each input file. - infilenames - collection of paths to sequence files """

    org_tetraz = {}
    for filename in infilenames:
        org = os.path.splitext(os.path.split(filename)[-1])[0]
        org_tetraz[org] = calculate_tetra_zscore(filename)
    return org_tetraz