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+---
+jupyter:
+  jupytext:
+    formats: md,ipynb
+    main_language: python
+    text_representation:
+      extension: .md
+      format_name: markdown
+      format_version: "1.3"
+      jupytext_version: 1.13.0
+  kernelspec:
+    display_name: "Python 3.9.5 64-bit ('.env': venv)"
+    name: python3
+---
+
+```python
+import context
+```
+
+```python
+import spacy
+```
+
+```python
+from edsnlp.connectors.omop import OmopConnector
+```
+
+```python
+
+```
+
+# Date detection
+
+```python
+text = (
+    "Le patient est arrivé le 23 août (23/08/2021). "
+    "Il dit avoir eu mal au ventre hier. "
+    "L'année dernière, on lui avait prescrit du doliprane."
+)
+```
+
+```python
+nlp = spacy.blank('fr')
+```
+
+```python
+nlp.add_pipe('normalizer')
+nlp.add_pipe('matcher', config=dict(regex=dict(word=r"(\w+)")))
+```
+
+```python
+doc = nlp(text)
+```
+
+```python
+doc._.note_id = 0
+```
+
+```python
+docs = []
+
+for i in range(10):
+    doc = nlp(f"Doc{i:02}" + text)
+    doc._.note_id = i
+    docs.append(doc)
+```
+
+```python
+connector = OmopConnector(nlp)
+```
+
+```python
+note, note_nlp = connector.docs2omop(docs)
+```
+
+```python
+note
+```
+
+```python
+new_docs = connector.omop2docs(note, note_nlp)
+```
+
+```python
+new_docs[0].text == docs[0].text
+```
+
+```python
+len(docs[0].ents) == len(new_docs[0].ents)
+```
+
+```python
+for e, o in zip(new_docs[0].ents, docs[0].ents):
+    assert e.text == o.text
+```
+
+```python
+
+```