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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 get_aggregation_propensity(self, email, password, cutoff_v=5, cutoff_n=5, run_amylmuts=False, outdir=None):
 """Run the AMYLPRED2 web server to calculate the aggregation propensity of this protein sequence, which is the number of aggregation-prone segments on the unfolded protein sequence. Stores statistics in the ``annotations`` attribute, under the key `aggprop-amylpred`. See :mod:`ssbio.protein.sequence.properties.aggregation_propensity` for instructions and details. """

        if not outdir:
            outdir = self.sequence_dir
            if not outdir:
                raise ValueError('Output directory must be specified')

        import ssbio.protein.sequence.properties.aggregation_propensity as agg

        agg_predictions = agg.AMYLPRED(email=email, password=password)
        result = agg_predictions.get_aggregation_propensity(seq=self, outdir=outdir,
                                                            cutoff_v=cutoff_v, cutoff_n=cutoff_n,
                                                            run_amylmuts=run_amylmuts)
        self.annotations['aggprop-amylpred'] = result