{% assign sizes = hash %}
{% assign sizes["S"] = "Small" %}
{% assign sizes["M"] = "Medium" %}
{% assign sizes["L"] = "Large" %}
{% assign size_abbreviations = sizes | keys %}
{% assign size_labels = sizes | values %}
{% for keyval in sizes %}
{% assign size_abbreviation = keyval[0] %}
{% assign size_label = keyval[1] %}
{{ size_abbreviation }}: {{ size_label }}
{% endfor %}