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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_choices_for(self, field):
 """ Get the choices for the given fields. Args: field (str):
 Name of field. Returns: """

        choices = self._fields[field].choices
        if isinstance(choices, six.string_types):
            return [(d['value'], d['name']) for d in self._choices_manager.get_all(choices)]
        else:
            return choices