diff --git a/Pipfile.lock b/Pipfile.lock
index 5c995c3..8a366e2 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -18,11 +18,11 @@
     "default": {
         "beautifulsoup4": {
             "hashes": [
-                "sha256:73cc4d115b96f79c7d77c1c7f7a0a8d4c57860d1041df407dd1aae7f07a77fd7",
-                "sha256:a6237df3c32ccfaee4fd201c8f5f9d9df619b93121d01353a64a73ce8c6ef9a8",
-                "sha256:e718f2342e2e099b640a34ab782407b7b676f47ee272d6739e60b8ea23829f2c"
+                "sha256:1edf5e39f3a5bc6e38b235b369128416c7239b34f692acccececb040233032a1",
+                "sha256:5dfe44f8fddc89ac5453f02659d3ab1668f2c0d9684839f0785037e8c6d9ac8d",
+                "sha256:645d833a828722357038299b7f6879940c11dddd95b900fe5387c258b72bb883"
             ],
-            "version": "==4.9.1"
+            "version": "==4.9.2"
         },
         "certifi": {
             "hashes": [
@@ -58,7 +58,6 @@
                 "sha256:0d78f8fde1c230e99fe37986a60526d7049ed4bf8a9fadbad5f00e22e58e041d",
                 "sha256:b2e5b40261e20f354d198eae92afc10d750afb487ed5e50f9c4eaf07c184146f"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
             "version": "==1.1"
         },
         "idna": {
@@ -66,7 +65,6 @@
                 "sha256:b307872f855b18632ce0c21c5e45be78c0ea7ae4c15c828c20788b26921eb3f6",
                 "sha256:b97d804b1e9b523befed77c48dacec60e6dcb0b5391d57af6a65a312a90648c0"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==2.10"
         },
         "isodate": {
@@ -110,7 +108,6 @@
                 "sha256:ecc930ae559ea8a43377e8b60ca6f8d61ac532fc57efb915d899de4a67928efd",
                 "sha256:f161af26f596131b63b236372e4ce40f3167c1b5b5d459b29d2514bd8c9dc9ee"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
             "version": "==4.5.2"
         },
         "mf2py": {
@@ -124,7 +121,6 @@
                 "sha256:c203ec8783bf771a155b207279b9bccb8dea02d8f0c9e5f8ead507bc3246ecc1",
                 "sha256:ef9d7589ef3c200abe66653d3f1ab1033c3c419ae9b9bdb1240a85b024efc88b"
             ],
-            "markers": "python_version >= '2.6' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==2.4.7"
         },
         "rdflib": {
@@ -153,7 +149,6 @@
                 "sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259",
                 "sha256:8b74bedcbbbaca38ff6d7491d76f2b06b3592611af620f8426e82dddb04a5ced"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.15.0"
         },
         "soupsieve": {
@@ -161,7 +156,7 @@
                 "sha256:1634eea42ab371d3d346309b93df7870a88610f0725d47528be902a0d95ecc55",
                 "sha256:a59dc181727e95d25f781f0eb4fd1825ff45590ec8ff49eadfd7f1a537cc0232"
             ],
-            "markers": "python_version >= '3.5'",
+            "markers": "python_version >= '3.0'",
             "version": "==2.0.1"
         },
         "urllib3": {
@@ -169,7 +164,6 @@
                 "sha256:91056c15fa70756691db97756772bb1eb9678fa585d9184f24534b100dc60f4a",
                 "sha256:e7983572181f5e1522d9c98453462384ee92a0be7fac5f1413a1e35c56cc0461"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4' and python_version < '4'",
             "version": "==1.25.10"
         },
         "w3lib": {
@@ -190,11 +184,10 @@
     "develop": {
         "attrs": {
             "hashes": [
-                "sha256:08a96c641c3a74e44eb59afb61a24f2cb9f4d7188748e76ba4bb5edfa3cb7d1c",
-                "sha256:f7b7ce16570fe9965acd6d30101a28f62fb4a7f9e926b3bbc9b61f8b04247e72"
+                "sha256:26b54ddbbb9ee1d34d5d3668dd37d6cf74990ab23c828c2888dccdceee395594",
+                "sha256:fce7fc47dfc976152e82d53ff92fa0407700c21acd20886a13777a0d20e655dc"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==19.3.0"
+            "version": "==20.2.0"
         },
         "iniconfig": {
             "hashes": [
@@ -203,20 +196,11 @@
             ],
             "version": "==1.0.1"
         },
-        "more-itertools": {
-            "hashes": [
-                "sha256:68c70cc7167bdf5c7c9d8f6954a7837089c6a36bf565383919bb595efb8a17e5",
-                "sha256:b78134b2063dd214000685165d81c154522c3ee0a1c0d4d113c80361c234c5a2"
-            ],
-            "markers": "python_version >= '3.5'",
-            "version": "==8.4.0"
-        },
         "packaging": {
             "hashes": [
                 "sha256:4357f74f47b9c12db93624a82154e9b120fa8293699949152b22065d556079f8",
                 "sha256:998416ba6962ae7fbd6596850b80e17859a5753ba17c32284f67bfff33784181"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==20.4"
         },
         "pluggy": {
@@ -224,7 +208,6 @@
                 "sha256:15b2acde666561e1298d71b523007ed7364de07029219b604cf808bfa1c765b0",
                 "sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==0.13.1"
         },
         "py": {
@@ -232,7 +215,6 @@
                 "sha256:366389d1db726cd2fcfc79732e75410e5fe4d31db13692115529d34069a043c2",
                 "sha256:9ca6883ce56b4e8da7e79ac18787889fa5206c79dcc67fb065376cd2fe03f342"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.9.0"
         },
         "pyparsing": {
@@ -240,23 +222,21 @@
                 "sha256:c203ec8783bf771a155b207279b9bccb8dea02d8f0c9e5f8ead507bc3246ecc1",
                 "sha256:ef9d7589ef3c200abe66653d3f1ab1033c3c419ae9b9bdb1240a85b024efc88b"
             ],
-            "markers": "python_version >= '2.6' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==2.4.7"
         },
         "pytest": {
             "hashes": [
-                "sha256:85228d75db9f45e06e57ef9bf4429267f81ac7c0d742cc9ed63d09886a9fe6f4",
-                "sha256:8b6007800c53fdacd5a5c192203f4e531eb2a1540ad9c752e052ec0f7143dbad"
+                "sha256:1cd09785c0a50f9af72220dd12aa78cfa49cbffc356c61eab009ca189e018a33",
+                "sha256:d010e24666435b39a4cf48740b039885642b6c273a3f77be3e7e03554d2806b7"
             ],
             "index": "pypi",
-            "version": "==6.0.1"
+            "version": "==6.1.0"
         },
         "six": {
             "hashes": [
                 "sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259",
                 "sha256:8b74bedcbbbaca38ff6d7491d76f2b06b3592611af620f8426e82dddb04a5ced"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.15.0"
         },
         "toml": {