if -%}
  {%- for author in contributors|unique -%}
  {%- set authordata = config.contributors.get(author, None) -%}
  {%- if authordata %}
    {%- set full_name = authordata.name.split(' ') -%}
    {{ full_name[-1] }}{{ self.comma() }}{{ full_name[0] }}{% if full_name|length > 2 %} {{ full_name[1:-1]|join(' ') }}{% endif %}{% if not loop.last %}{{ self.and() }}{% endif %}
  {%- else %}
    {%- set full_name = author.split(' ') -%}
    {{ full_name[-1] }}{{ self.comma() }}{{ full_name[0] }}{% if full_name|le