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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 bind_name(self, name):
 """Bind field to its name in model class."""

        if self.name:
            raise errors.Error('Already bound "{0}" with name "{1}" could not '
                               'be rebound'.format(self, self.name))
        self.name = name
        self.storage_name = ''.join(('_', self.name))
        return self