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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 _full_path(self, path_info):
 """Return the full path from which to read."""

        full_path = self.root + path_info
        if path.exists(full_path):
            return full_path
        else:
            for magic in self.magics:
                if path.exists(magic.new_path(full_path)):
                    return magic.new_path(full_path)
            else:
                return full_path