Added loader for sample data

eyepy/data/__init__.py

@@ -0,0 +1,25 @@
+import urllib.request
+import zipfile
+from pathlib import Path
+
+import eyepy.io as epio
+
+SAMPLE_DATA = {"drusen_patient":
+                   ('https://uni-bonn.sciebo.de/s/VD8CPAgDKp2EYlm/download',
+                    epio.read_xml)}
+
+EYEPY_DATA_DIR = Path("~/.eyepy/data").expanduser()
+if not EYEPY_DATA_DIR.is_dir():
+    EYEPY_DATA_DIR.mkdir(parents=True)
+
+
+def load(name):
+    data_dir = (EYEPY_DATA_DIR / name)
+    if not data_dir.is_dir():
+        download_path = EYEPY_DATA_DIR / (name + ".zip")
+        urllib.request.urlretrieve(SAMPLE_DATA[name][0], download_path)
+        with zipfile.ZipFile(download_path, 'r') as zip_ref:
+            zip_ref.extractall(EYEPY_DATA_DIR)
+        download_path.unlink()
+
+    return SAMPLE_DATA[name][1](EYEPY_DATA_DIR / name / "metaclean.xml")