Remove numpy requirement from setup.py since TensorFlow and TFLite_runtime require different versions. If both are installed, use the tflite interpreter built into tensorflow instead of the tflite_runtime one.

Author: mbeissinger

setup.py

@@ -20,7 +20,6 @@
     mac_version = None
 
 requirements = [
-    "numpy~=1.19.5",
     "pillow~=8.3.1",
     "requests"
 ]

src/lobe/backends/backend_tflite.py

@@ -3,14 +3,17 @@
 from ..signature_constants import TENSOR_NAME
 from ..utils import decode_dict_bytes_as_str
 
+# first try to import the tflite interpreter from TensorFlow base library (if we have both installed) to avoid a collision
 try:
-    import tflite_runtime.interpreter as tflite
-
+    import tensorflow.lite as tflite
 except ImportError:
-    # Needs better error text
-    raise ImportError(
-        "ERROR: This is a TensorFlow Lite model and requires TensorFlow Lite interpreter to be installed on this device. Please install lobe-python with lobe[tflite] or lobe[all] options. If that doesn't work, please go to https://www.tensorflow.org/lite/guide/python and download the appropriate version for you device."
-    )
+    try:
+        import tflite_runtime.interpreter as tflite
+
+    except ImportError:
+        raise ImportError(
+            "ERROR: This is a TensorFlow Lite model and requires TensorFlow Lite interpreter to be installed on this device. Please install lobe-python with lobe[tflite] or lobe[all] options. If that doesn't work, please go to https://www.tensorflow.org/lite/guide/python and download the appropriate version for you device."
+        )
 
 
 class TFLiteModel(object):