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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 from_binary(cls,pst,filename):
 """instantiate an observation obsemble from a jco-type file Parameters pst : pyemu.Pst a Pst instance filename : str the binary file name Returns ------- oe : ObservationEnsemble """

        m = Matrix.from_binary(filename)
        return ObservationEnsemble(data=m.x,pst=pst, index=m.row_names)