Add Snips Inference Module

Add slightly modified version of the original Snips NLU
library. This module adds support for Python upto version
3.10.

Bug-AGL: SPEC-4856
Signed-off-by: Malik Talha <talhamalik727x@gmail.com>
Change-Id: I6d7e9eb181e6ff4aed9b6291027877ccb9f0d846

1 files changed, 69 insertions, 0 deletions

diff --git a/snips_inference_agl/slot_filler/feature.py b/snips_inference_agl/slot_filler/feature.py
new file mode 100644
index 0000000..a6da552
--- /dev/null
+++ b/snips_inference_agl/slot_filler/feature.py
@@ -0,0 +1,69 @@
+from __future__ import unicode_literals
+
+from builtins import object
+
+TOKEN_NAME = "token"
+
+
+class Feature(object):
+    """CRF Feature which is used by :class:`.CRFSlotFiller`
+
+    Attributes:
+        base_name (str): Feature name (e.g. 'is_digit', 'is_first' etc)
+        func (function): The actual feature function for example:
+
+            def is_first(tokens, token_index):
+                return "1" if token_index == 0 else None
+
+        offset (int, optional): Token offset to consider when computing
+            the feature (e.g -1 for computing the feature on the previous word)
+        drop_out (float, optional): Drop out to use when computing the
+            feature during training
+
+    Note:
+        The easiest way to add additional features to the existing ones is
+        to create a :class:`.CRFFeatureFactory`
+    """
+
+    def __init__(self, base_name, func, offset=0, drop_out=0):
+        if base_name == TOKEN_NAME:
+            raise ValueError("'%s' name is reserved" % TOKEN_NAME)
+        self.offset = offset
+        self._name = None
+        self._base_name = None
+        self.base_name = base_name
+        self.function = func
+        self.drop_out = drop_out
+
+    @property
+    def name(self):
+        return self._name
+
+    @property
+    def base_name(self):
+        return self._base_name
+
+    @base_name.setter
+    def base_name(self, value):
+        self._name = _offset_name(value, self.offset)
+        self._base_name = _offset_name(value, 0)
+
+    def compute(self, token_index, cache):
+        if not 0 <= (token_index + self.offset) < len(cache):
+            return None
+
+        if self.base_name in cache[token_index + self.offset]:
+            return cache[token_index + self.offset][self.base_name]
+
+        tokens = [c["token"] for c in cache]
+        value = self.function(tokens, token_index + self.offset)
+        cache[token_index + self.offset][self.base_name] = value
+        return value
+
+
+def _offset_name(name, offset):
+    if offset > 0:
+        return "%s[+%s]" % (name, offset)
+    if offset < 0:
+        return "%s[%s]" % (name, offset)
+    return name