diff --git a/cms_bluebutton/auth.py b/cms_bluebutton/auth.py
index 808597a..de266a1 100755
--- a/cms_bluebutton/auth.py
+++ b/cms_bluebutton/auth.py
@@ -51,27 +51,18 @@ def set_dict(self, auth_token_dict):
         self.token_type = auth_token_dict.get("token_type")
 
 
-def refresh_auth_token(bb, auth_token):
+def refresh_auth_token(bb, auth_token) -> AuthorizationToken:
     data = {
         "client_id": bb.client_id,
         "grant_type": "refresh_token",
         "refresh_token": auth_token.refresh_token,
     }
-
-    headers = SDK_HEADERS
-
-    token_response = requests.post(
-        url=bb.auth_token_url,
-        data=data,
-        headers=headers,
-        auth=(bb.client_id, bb.client_secret),
-    )
-
+    token_response = _do_post(data, bb, (bb.client_id, bb.client_secret))
     token_response.raise_for_status()
     return AuthorizationToken(token_response.json())
 
 
-def generate_authorize_url(bb, auth_data):
+def generate_authorize_url(bb, auth_data) -> str:
     params = {
         "client_id": bb.client_id,
         "redirect_uri": bb.callback_url,
@@ -94,13 +85,13 @@ def base64_url_encode(buffer):
     return buffer_result
 
 
-def get_random_string(length):
+def get_random_string(length) -> str:
     letters = string.ascii_letters + string.digits + string.punctuation
     result = "".join(random.choice(letters) for i in range(length))
     return result
 
 
-def generate_pkce_data():
+def generate_pkce_data() -> dict:
     verifier = generate_random_state(32)
     code_challenge = base64.urlsafe_b64encode(
         hashlib.sha256(verifier.encode("ASCII")).digest()
@@ -108,17 +99,17 @@ def generate_pkce_data():
     return {"code_challenge": code_challenge.decode("utf-8"), "verifier": verifier}
 
 
-def generate_random_state(num):
+def generate_random_state(num) -> str:
     return base64_url_encode(get_random_string(num))
 
 
-def generate_auth_data():
+def generate_auth_data() -> dict:
     auth_data = {"state": generate_random_state(32)}
     auth_data.update(generate_pkce_data())
     return auth_data
 
 
-def get_access_token_from_code(bb, auth_data, callback_code):
+def get_access_token_from_code(bb, auth_data, callback_code) -> dict:
     data = {
         "client_id": bb.client_id,
         "client_secret": bb.client_secret,
@@ -129,14 +120,7 @@ def get_access_token_from_code(bb, auth_data, callback_code):
         "code_challenge": auth_data["code_challenge"],
     }
 
-    mp_encoder = MultipartEncoder(data)
-    headers = SDK_HEADERS
-    headers["content-type"] = mp_encoder.content_type
-    token_response = requests.post(
-        url=bb.auth_token_url,
-        data=mp_encoder,
-        headers=headers
-    )
+    token_response = _do_post(data, bb, None)
     token_response.raise_for_status()
     token_dict = token_response.json()
     token_dict["expires_at"] = datetime.datetime.now(
@@ -157,3 +141,19 @@ def get_authorization_token(bb, auth_data, callback_code, callback_state):
         raise ValueError("Provided callback state does not match.")
 
     return AuthorizationToken(get_access_token_from_code(bb, auth_data, callback_code))
+
+
+def _do_post(data, bb, auth):
+    mp_encoder = MultipartEncoder(data)
+    headers = SDK_HEADERS
+    headers["content-type"] = mp_encoder.content_type
+    return requests.post(
+        url=bb.auth_token_url,
+        data=mp_encoder,
+        headers=headers
+    ) if not auth else requests.post(
+        url=bb.auth_token_url,
+        data=mp_encoder,
+        headers=headers,
+        auth=auth
+    )
diff --git a/requirements/req.dev.in b/requirements/req.dev.in
index 3999596..4e8297d 100644
--- a/requirements/req.dev.in
+++ b/requirements/req.dev.in
@@ -1,3 +1,4 @@
+pyyaml==5.4.1
 requests==2.27.1
 requests-mock==1.9.3
 requests-toolbelt==0.9.1
diff --git a/requirements/req.dev.txt b/requirements/req.dev.txt
index f40b020..28afb81 100644
--- a/requirements/req.dev.txt
+++ b/requirements/req.dev.txt
@@ -103,6 +103,37 @@ pytest==7.0.1 \
     --hash=sha256:9ce3ff477af913ecf6321fe337b93a2c0dcf2a0a1439c43f5452112c1e4280db \
     --hash=sha256:e30905a0c131d3d94b89624a1cc5afec3e0ba2fbdb151867d8e0ebd49850f171
     # via -r requirements/req.dev.in
+pyyaml==5.4.1 \
+    --hash=sha256:08682f6b72c722394747bddaf0aa62277e02557c0fd1c42cb853016a38f8dedf \
+    --hash=sha256:0f5f5786c0e09baddcd8b4b45f20a7b5d61a7e7e99846e3c799b05c7c53fa696 \
+    --hash=sha256:129def1b7c1bf22faffd67b8f3724645203b79d8f4cc81f674654d9902cb4393 \
+    --hash=sha256:294db365efa064d00b8d1ef65d8ea2c3426ac366c0c4368d930bf1c5fb497f77 \
+    --hash=sha256:3b2b1824fe7112845700f815ff6a489360226a5609b96ec2190a45e62a9fc922 \
+    --hash=sha256:3bd0e463264cf257d1ffd2e40223b197271046d09dadf73a0fe82b9c1fc385a5 \
+    --hash=sha256:4465124ef1b18d9ace298060f4eccc64b0850899ac4ac53294547536533800c8 \
+    --hash=sha256:49d4cdd9065b9b6e206d0595fee27a96b5dd22618e7520c33204a4a3239d5b10 \
+    --hash=sha256:4e0583d24c881e14342eaf4ec5fbc97f934b999a6828693a99157fde912540cc \
+    --hash=sha256:5accb17103e43963b80e6f837831f38d314a0495500067cb25afab2e8d7a4018 \
+    --hash=sha256:607774cbba28732bfa802b54baa7484215f530991055bb562efbed5b2f20a45e \
+    --hash=sha256:6c78645d400265a062508ae399b60b8c167bf003db364ecb26dcab2bda048253 \
+    --hash=sha256:72a01f726a9c7851ca9bfad6fd09ca4e090a023c00945ea05ba1638c09dc3347 \
+    --hash=sha256:74c1485f7707cf707a7aef42ef6322b8f97921bd89be2ab6317fd782c2d53183 \
+    --hash=sha256:895f61ef02e8fed38159bb70f7e100e00f471eae2bc838cd0f4ebb21e28f8541 \
+    --hash=sha256:8c1be557ee92a20f184922c7b6424e8ab6691788e6d86137c5d93c1a6ec1b8fb \
+    --hash=sha256:bb4191dfc9306777bc594117aee052446b3fa88737cd13b7188d0e7aa8162185 \
+    --hash=sha256:bfb51918d4ff3d77c1c856a9699f8492c612cde32fd3bcd344af9be34999bfdc \
+    --hash=sha256:c20cfa2d49991c8b4147af39859b167664f2ad4561704ee74c1de03318e898db \
+    --hash=sha256:cb333c16912324fd5f769fff6bc5de372e9e7a202247b48870bc251ed40239aa \
+    --hash=sha256:d2d9808ea7b4af864f35ea216be506ecec180628aced0704e34aca0b040ffe46 \
+    --hash=sha256:d483ad4e639292c90170eb6f7783ad19490e7a8defb3e46f97dfe4bacae89122 \
+    --hash=sha256:dd5de0646207f053eb0d6c74ae45ba98c3395a571a2891858e87df7c9b9bd51b \
+    --hash=sha256:e1d4970ea66be07ae37a3c2e48b5ec63f7ba6804bdddfdbd3cfd954d25a82e63 \
+    --hash=sha256:e4fac90784481d221a8e4b1162afa7c47ed953be40d31ab4629ae917510051df \
+    --hash=sha256:fa5ae20527d8e831e8230cbffd9f8fe952815b2b7dae6ffec25318803a7528fc \
+    --hash=sha256:fd7f6999a8070df521b6384004ef42833b9bd62cfee11a09bda1079b4b704247 \
+    --hash=sha256:fdc842473cd33f45ff6bce46aea678a54e3d21f1b61a7750ce3c498eedfe25d6 \
+    --hash=sha256:fe69978f3f768926cfa37b867e3843918e012cf83f680806599ddce33c2c68b0
+    # via -r requirements/req.dev.in
 requests==2.27.1 \
     --hash=sha256:68d7c56fd5a8999887728ef304a6d12edc7be74f1cfa47714fc8b414525c9a61 \
     --hash=sha256:f22fa1e554c9ddfd16e6e41ac79759e17be9e492b3587efa038054674760e72d