Document the data parsing function

src/model.py

@@ -1,6 +1,11 @@
 from tensorflow_io import genome
+from tensorflow import Tensor
+from typing import Tuple
 
 
-def parse_data(filepath):
+def parse_data(filepath) -> Tuple[Tensor, Tensor]:
+    """
+    Reads a FASTQ file and returns the sequences and the qualities
+    """
     HVR = genome.read_fastq(filename=filepath)
     return HVR.sequences, HVR.raw_quality