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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 align(self, out_path=None):
 """We align the sequences in the fasta file with muscle."""

        if out_path is None: out_path = self.prefix_path + '.aln'
        sh.muscle38("-in", self.path, "-out", out_path)
        return AlignedFASTA(out_path)