def add_section(self, section_name):
        """Create a section of the report, to be headed by section_name

        Text and images can be added by using the `section` argument of the
        `add_text` and `add_image` methods. Sections can also be ordered by
        using the `set_section_order` method.

        By default, text and images that have no section will be placed after
        all the sections, in the order they were added. This behavior may be
        altered using the `sections_first` attribute of the `make_report`
        method.
        """
        self.section_headings.append(section_name)
        if section_name in self.sections:
            raise ValueError("Section %s already exists." % section_name)
        self.sections[section_name] = []
        return
Create a section of the report, to be headed by section_name

        Text and images can be added by using the `section` argument of the
        `add_text` and `add_image` methods. Sections can also be ordered by
        using the `set_section_order` method.

        By default, text and images that have no section will be placed after
        all the sections, in the order they were added. This behavior may be
        altered using the `sections_first` attribute of the `make_report`
        method.