diff --git a/Pipfile b/Pipfile
index c97ec297b..95d845d1f 100644
--- a/Pipfile
+++ b/Pipfile
@@ -35,6 +35,8 @@ psycopg2-binary = "*"
 redis = "*"
 # Pinned because aarch64 wheels and updates cause warnings when loading the classifier model.
 scikit-learn="==0.24.0"
+# Prevent scipy updates because 1.6 is incompatible with python 3.6
+scipy="~=1.5.4"
 whitenoise = "~=5.2.0"
 watchdog = "*"
 whoosh="~=2.7.4"
diff --git a/Pipfile.lock b/Pipfile.lock
index 5ae121105..b8cb29b29 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "33586bca793586bd4e413ae634780628b6df65a0d67b581c86ab4d2a16a817e0"
+            "sha256": "d80d2539a4528a8fd9e848875c2e2d5bcdb3e98154f45b612706094b84ecaaea"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -416,6 +416,14 @@
             ],
             "version": "==0.4.0"
         },
+        "importlib-metadata": {
+            "hashes": [
+                "sha256:ace61d5fc652dc280e7b6b4ff732a9c2d40db2c0f92bc6cb74e07b73d53a1771",
+                "sha256:fa5daa4477a7414ae34e95942e4dd07f62adf589143c875c133c1e53c4eff38d"
+            ],
+            "markers": "python_version < '3.8'",
+            "version": "==3.4.0"
+        },
         "incremental": {
             "hashes": [
                 "sha256:717e12246dddf231a349175f48d74d93e2897244939173b01974ab6661406b9f",
@@ -1005,29 +1013,35 @@
         },
         "scipy": {
             "hashes": [
-                "sha256:155225621df90fcd151e25d51c50217e412de717475999ebb76e17e310176981",
-                "sha256:1bc5b446600c4ff7ab36bade47180673141322f0febaa555f1c433fe04f2a0e3",
-                "sha256:2f1c2ebca6fd867160e70102200b1bd07b3b2d31a3e6af3c58d688c15d0d07b7",
-                "sha256:313785c4dab65060f9648112d025f6d2fec69a8a889c714328882d678a95f053",
-                "sha256:31ab217b5c27ab429d07428a76002b33662f98986095bbce5d55e0788f7e8b15",
-                "sha256:3d4303e3e21d07d9557b26a1707bb9fc065510ee8501c9bf22a0157249a82fd0",
-                "sha256:4f1d9cc977ac6a4a63c124045c1e8bf67ec37098f67c699887a93736961a00ae",
-                "sha256:58731bbe0103e96b89b2f41516699db9b63066e4317e31b8402891571f6d358f",
-                "sha256:8629135ee00cc2182ac8be8e75643b9f02235942443732c2ed69ab48edcb6614",
-                "sha256:876badc33eec20709d4e042a09834f5953ebdac4088d45a4f3a1f18b56885718",
-                "sha256:8840a9adb4ede3751f49761653d3ebf664f25195fdd42ada394ffea8903dd51d",
-                "sha256:aef3a2dbc436bbe8f6e0b635f0b5fe5ed024b522eee4637dbbe0b974129ca734",
-                "sha256:b8af26839ae343655f3ca377a5d5e5466f1d3b3ac7432a43449154fe958ae0e0",
-                "sha256:c0911f3180de343643f369dc5cfedad6ba9f939c2d516bddea4a6871eb000722",
-                "sha256:cb6dc9f82dfd95f6b9032a8d7ea70efeeb15d5b5fd6ed4e8537bb3c673580566",
-                "sha256:cdbc47628184a0ebeb5c08f1892614e1bd4a51f6e0d609c6eed253823a960f5b",
-                "sha256:d902d3a5ad7f28874c0a82db95246d24ca07ad932741df668595fe00a4819870",
-                "sha256:eab389aba0ad8b5e6b5abdc3337ade46823df75f80a8edd4c67833567577cb3d",
-                "sha256:eb7928275f3560d47e5538e15e9f32b3d64cd30ea8f85f3e82987425476f53f6",
-                "sha256:f68d5761a2d2376e2b194c8e9192bbf7c51306ca176f1a0889990a52ef0d551f"
+                "sha256:168c45c0c32e23f613db7c9e4e780bc61982d71dcd406ead746c7c7c2f2004ce",
+                "sha256:213bc59191da2f479984ad4ec39406bf949a99aba70e9237b916ce7547b6ef42",
+                "sha256:25b241034215247481f53355e05f9e25462682b13bd9191359075682adcd9554",
+                "sha256:2c872de0c69ed20fb1a9b9cf6f77298b04a26f0b8720a5457be08be254366c6e",
+                "sha256:3397c129b479846d7eaa18f999369a24322d008fac0782e7828fa567358c36ce",
+                "sha256:368c0f69f93186309e1b4beb8e26d51dd6f5010b79264c0f1e9ca00cd92ea8c9",
+                "sha256:3d5db5d815370c28d938cf9b0809dade4acf7aba57eaf7ef733bfedc9b2474c4",
+                "sha256:4598cf03136067000855d6b44d7a1f4f46994164bcd450fb2c3d481afc25dd06",
+                "sha256:4a453d5e5689de62e5d38edf40af3f17560bfd63c9c5bd228c18c1f99afa155b",
+                "sha256:4f12d13ffbc16e988fa40809cbbd7a8b45bc05ff6ea0ba8e3e41f6f4db3a9e47",
+                "sha256:634568a3018bc16a83cda28d4f7aed0d803dd5618facb36e977e53b2df868443",
+                "sha256:65923bc3809524e46fb7eb4d6346552cbb6a1ffc41be748535aa502a2e3d3389",
+                "sha256:6b0ceb23560f46dd236a8ad4378fc40bad1783e997604ba845e131d6c680963e",
+                "sha256:8c8d6ca19c8497344b810b0b0344f8375af5f6bb9c98bd42e33f747417ab3f57",
+                "sha256:9ad4fcddcbf5dc67619379782e6aeef41218a79e17979aaed01ed099876c0e62",
+                "sha256:a254b98dbcc744c723a838c03b74a8a34c0558c9ac5c86d5561703362231107d",
+                "sha256:b03c4338d6d3d299e8ca494194c0ae4f611548da59e3c038813f1a43976cb437",
+                "sha256:b5e9d3e4474644915809d6aa1416ff20430a3ed9ae723a5d295da5ddb24985e2",
+                "sha256:cc1f78ebc982cd0602c9a7615d878396bec94908db67d4ecddca864d049112f2",
+                "sha256:d6d25c41a009e3c6b7e757338948d0076ee1dd1770d1c09ec131f11946883c54",
+                "sha256:d84cadd7d7998433334c99fa55bcba0d8b4aeff0edb123b2a1dfcface538e474",
+                "sha256:e360cb2299028d0b0d0f65a5c5e51fc16a335f1603aa2357c25766c8dab56938",
+                "sha256:e98d49a5717369d8241d6cf33ecb0ca72deee392414118198a8e5b4c35c56340",
+                "sha256:ed572470af2438b526ea574ff8f05e7f39b44ac37f712105e57fc4d53a6fb660",
+                "sha256:f87b39f4d69cf7d7529d7b1098cb712033b17ea7714aed831b95628f483fd012",
+                "sha256:fa789583fc94a7689b45834453fec095245c7e69c58561dc159b5d5277057e4c"
             ],
-            "markers": "python_version >= '3.7'",
-            "version": "==1.6.0"
+            "index": "pypi",
+            "version": "==1.5.4"
         },
         "service-identity": {
             "hashes": [
@@ -1125,6 +1139,15 @@
             "markers": "python_version >= '3.6'",
             "version": "==20.12.1"
         },
+        "typing-extensions": {
+            "hashes": [
+                "sha256:7cb407020f00f7bfc3cb3e7881628838e69d8f3fcab2f64742a5e76b2f841918",
+                "sha256:99d4073b617d30288f569d3f13d2bd7548c3a7e4c8de87db09a9d29bb3a4a60c",
+                "sha256:dafc7639cde7f1b6e1acc0f457842a83e722ccca8eef5270af2d74792619a89f"
+            ],
+            "markers": "python_version < '3.8'",
+            "version": "==3.7.4.3"
+        },
         "tzlocal": {
             "hashes": [
                 "sha256:643c97c5294aedc737780a49d9df30889321cbe1204eac2c2ec6134035a92e44",
@@ -1250,6 +1273,14 @@
             "index": "pypi",
             "version": "==2.7.4"
         },
+        "zipp": {
+            "hashes": [
+                "sha256:102c24ef8f171fd729d46599845e95c7ab894a4cf45f5de11a44cc7444fb1108",
+                "sha256:ed5eee1974372595f9e416cc7bbeeb12335201d8081ca8a0743c954d4446e5cb"
+            ],
+            "markers": "python_version >= '3.6'",
+            "version": "==3.4.0"
+        },
         "zope.interface": {
             "hashes": [
                 "sha256:05a97ba92c1c7c26f25c9f671aa1ef85ffead6cdad13770e5b689cf983adc7e1",
@@ -1501,6 +1532,22 @@
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.2.0"
         },
+        "importlib-metadata": {
+            "hashes": [
+                "sha256:ace61d5fc652dc280e7b6b4ff732a9c2d40db2c0f92bc6cb74e07b73d53a1771",
+                "sha256:fa5daa4477a7414ae34e95942e4dd07f62adf589143c875c133c1e53c4eff38d"
+            ],
+            "markers": "python_version < '3.8'",
+            "version": "==3.4.0"
+        },
+        "importlib-resources": {
+            "hashes": [
+                "sha256:885b8eae589179f661c909d699a546cf10d83692553e34dca1bf5eb06f7f6217",
+                "sha256:bfdad047bce441405a49cf8eb48ddce5e56c696e185f59147a8b79e75e9e6380"
+            ],
+            "markers": "python_version < '3.7'",
+            "version": "==5.1.0"
+        },
         "iniconfig": {
             "hashes": [
                 "sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3",
@@ -1797,6 +1844,15 @@
             "index": "pypi",
             "version": "==3.21.2"
         },
+        "typing-extensions": {
+            "hashes": [
+                "sha256:7cb407020f00f7bfc3cb3e7881628838e69d8f3fcab2f64742a5e76b2f841918",
+                "sha256:99d4073b617d30288f569d3f13d2bd7548c3a7e4c8de87db09a9d29bb3a4a60c",
+                "sha256:dafc7639cde7f1b6e1acc0f457842a83e722ccca8eef5270af2d74792619a89f"
+            ],
+            "markers": "python_version < '3.8'",
+            "version": "==3.7.4.3"
+        },
         "urllib3": {
             "hashes": [
                 "sha256:1b465e494e3e0d8939b50680403e3aedaa2bc434b7d5af64dfd3c958d7f5ae80",
@@ -1812,6 +1868,14 @@
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==20.4.0"
+        },
+        "zipp": {
+            "hashes": [
+                "sha256:102c24ef8f171fd729d46599845e95c7ab894a4cf45f5de11a44cc7444fb1108",
+                "sha256:ed5eee1974372595f9e416cc7bbeeb12335201d8081ca8a0743c954d4446e5cb"
+            ],
+            "markers": "python_version >= '3.6'",
+            "version": "==3.4.0"
         }
     }
 }
diff --git a/requirements.txt b/requirements.txt
index c0228d378..0c6deff1d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -44,6 +44,7 @@ hyperlink==21.0.0
 idna==2.10; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
 imap-tools==0.36.0
 img2pdf==0.4.0
+importlib-metadata==3.4.0; python_version < '3.8'
 incremental==17.5.0
 inotify-simple==1.3.5; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
 inotifyrecursive==0.3.5
@@ -77,7 +78,7 @@ regex==2020.11.13
 reportlab==3.5.60
 requests==2.25.1; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'
 scikit-learn==0.24.0
-scipy==1.6.0; python_version >= '3.7'
+scipy==1.5.4
 service-identity==18.1.0
 six==1.15.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
 sortedcontainers==2.3.0
@@ -87,6 +88,7 @@ tika==1.24
 tqdm==4.56.0
 twisted[tls]==20.3.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'
 txaio==20.12.1; python_version >= '3.6'
+typing-extensions==3.7.4.3; python_version < '3.8'
 tzlocal==2.1
 urllib3==1.26.3; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4' and python_version < '4'
 uvicorn[standard]==0.13.3
@@ -97,4 +99,5 @@ wcwidth==0.2.5
 websockets==8.1
 whitenoise==5.2.0
 whoosh==2.7.4
+zipp==3.4.0; python_version >= '3.6'
 zope.interface==5.2.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'