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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_colorscheme(self, scheme_file):
 """Return a string object with the colorscheme that is to be inserted."""

        scheme = get_yaml_dict(scheme_file)
        scheme_slug = builder.slugify(scheme_file)
        builder.format_scheme(scheme, scheme_slug)

        try:
            temp_base, temp_sub = self.temp.split('##')
        except ValueError:
            temp_base, temp_sub = (self.temp.strip('##'), 'default')

        temp_path = rel_to_cwd('templates', temp_base)
        temp_group = builder.TemplateGroup(temp_path)
        try:
            single_temp = temp_group.templates[temp_sub]
        except KeyError:
            raise FileNotFoundError(None,
                                    None,
                                    self.path + ' (sub-template)')

        colorscheme = pystache.render(single_temp['parsed'], scheme)
        return colorscheme