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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 make_field(self, field_name, field_body):
 """Fill content into nodes. :param string field_name: Field name of the field :param field_name: Field body if the field :type field_name: str or instance of docutils.nodes :return: field instance filled with given name and body :rtype: nodes.field """

        name = nodes.field_name()
        name += nodes.Text(field_name)

        paragraph = nodes.paragraph()
        if isinstance(field_body, str):
            # This is the case when field_body is just a string:
            paragraph += nodes.Text(field_body)
        else:
            # This is the case when field_body is a complex node:
            # useful when constructing nested field lists
            paragraph += field_body

        body = nodes.field_body()
        body += paragraph

        field = nodes.field()
        field.extend([name, body])
        return field