Add PIAF (#774)

* add original prompts

* update metrics

Author: KhalidAlt

promptsource/templates/piaf/templates.yaml

@@ -0,0 +1,80 @@
+dataset: piaf
+templates:
+  4bac0d14-ac52-442c-9364-ea7add071af4: !Template
+    answer_choices: null
+    id: 4bac0d14-ac52-442c-9364-ea7add071af4
+    jinja: 'Extract from the passage the answer to this question: {{question}}
+
+      Passage about {{title}}: {{context}} ||| {{answers[''text''][0]}}'
+    metadata: !TemplateMetadata
+      choices_in_prompt: false
+      metrics:
+      - Accuracy
+      - Squad
+      original_task: true
+    name: extract_the_answer
+    reference: ''
+  723aa38b-c671-457c-96ee-bf449184f57f: !Template
+    answer_choices: null
+    id: 723aa38b-c671-457c-96ee-bf449184f57f
+    jinja: '{{title}}
+
+      {{context}}
+
+      Q: {{question}}
+
+
+      A: ||| {{answers.text[0]}}'
+    metadata: !TemplateMetadata
+      choices_in_prompt: false
+      metrics:
+      - Accuracy
+      - Squad
+      original_task: true
+    name: context_follow_q
+    reference: ''
+  9f4bf5cd-070c-46a1-9098-2ad1ef63d806: !Template
+    answer_choices: null
+    id: 9f4bf5cd-070c-46a1-9098-2ad1ef63d806
+    jinja: "Given the following passage answer the question that follows: \n{{context}}\n\
+      {{question}} ||| {{answers.text[0]}}"
+    metadata: !TemplateMetadata
+      choices_in_prompt: false
+      metrics:
+      - Accuracy
+      - Squad
+      original_task: true
+    name: given_passage_answer
+    reference: ''
+  bdeaa285-287f-44de-9bff-49dbf533be89: !Template
+    answer_choices: null
+    id: bdeaa285-287f-44de-9bff-49dbf533be89
+    jinja: '{{context}}
+
+
+      Given the above context, {{question}} ||| {{answers.text[0]}}'
+    metadata: !TemplateMetadata
+      choices_in_prompt: false
+      metrics:
+      - Accuracy
+      - Squad
+      original_task: true
+    name: Given_above_context
+    reference: ''
+  ec70d9f8-edd5-4b8c-b18a-a5a7fb962b9a: !Template
+    answer_choices: null
+    id: ec70d9f8-edd5-4b8c-b18a-a5a7fb962b9a
+    jinja: 'After reading the following paragraph, please answer the question that
+      follows:
+
+      {{context}}
+
+      {{question}} ||| {{answers.text[0]}}'
+    metadata: !TemplateMetadata
+      choices_in_prompt: false
+      metrics:
+      - Accuracy
+      - Squad
+      original_task: true
+    name: after_reading
+    reference: ''