diff --git a/certbot-apache/certbot_apache/_internal/apache_util.py b/certbot-apache/certbot_apache/_internal/apache_util.py
index 4c1a9b250..f6cb00e3c 100644
--- a/certbot-apache/certbot_apache/_internal/apache_util.py
+++ b/certbot-apache/certbot_apache/_internal/apache_util.py
@@ -3,8 +3,6 @@ import binascii
 import struct
 import time
 
-import six
-
 from certbot import crypto_util
 from certbot import util
 from certbot.compat import os
@@ -25,6 +23,7 @@ def get_apache_ocsp_struct(ttl, ocsp_response):
     ttl_struct = struct.pack('l', int(ttl*1000000))
     return b'\x01'.join([ttl_struct, ocsp_response])
 
+
 def certid_sha1_hex(cert_path):
     """Hex representation of certificate SHA1 fingerprint
 
@@ -35,9 +34,7 @@ def certid_sha1_hex(cert_path):
 
     """
     sha1_hex = binascii.hexlify(certid_sha1(cert_path))
-    if isinstance(sha1_hex, six.binary_type):
-        return sha1_hex.decode('utf-8')  # pragma: no cover
-    return sha1_hex  # pragma: no cover
+    return sha1_hex.decode('utf-8')
 
 
 def certid_sha1(cert_path):
@@ -51,6 +48,7 @@ def certid_sha1(cert_path):
     """
     return crypto_util.cert_sha1_fingerprint(cert_path)
 
+
 def get_mod_deps(mod_name):
     """Get known module dependencies.
 
diff --git a/certbot-apache/certbot_apache/_internal/constants.py b/certbot-apache/certbot_apache/_internal/constants.py
index e75435b76..92becff32 100644
--- a/certbot-apache/certbot_apache/_internal/constants.py
+++ b/certbot-apache/certbot_apache/_internal/constants.py
@@ -69,7 +69,7 @@ MANAGED_COMMENT_ID = MANAGED_COMMENT+", VirtualHost id: {0}"
 """Managed by Certbot comments and the VirtualHost identification template"""
 
 OCSP_APACHE_TTL = 432000
-"""Apache TTL for OCSP response: 5 days"""
+"""Apache TTL for OCSP response in seconds: 5 days"""
 
 OCSP_INTERNAL_TTL = 86400
-"""Internal TTL for OCSP response: 1 day"""
+"""Internal TTL for OCSP response in seconds: 1 day"""
diff --git a/certbot-apache/certbot_apache/_internal/prefetch_ocsp.py b/certbot-apache/certbot_apache/_internal/prefetch_ocsp.py
index 00219f052..f25ffc2ca 100644
--- a/certbot-apache/certbot_apache/_internal/prefetch_ocsp.py
+++ b/certbot-apache/certbot_apache/_internal/prefetch_ocsp.py
@@ -143,7 +143,7 @@ class OCSPPrefetchMixin(object):
         :rtype: int
         """
 
-        if next_update:
+        if next_update is not None:
             now = time.time()
             res_ttl = int(time.mktime(next_update.timetuple()) - now)
             if res_ttl > 0:
diff --git a/certbot/certbot/_internal/ocsp.py b/certbot/certbot/_internal/ocsp.py
index 10789776c..c70692f19 100644
--- a/certbot/certbot/_internal/ocsp.py
+++ b/certbot/certbot/_internal/ocsp.py
@@ -77,6 +77,7 @@ class RevocationChecker(object):
 
         :param str cert_path: Certificate path
         :param str chain_path: Certificate chain filepath
+        :param str response_file: File path to a file containing a raw OCSP response.
 
         :returns: True if revoked; False if valid or the check failed or cert is expired.
         :rtype: bool
diff --git a/certbot/certbot/crypto_util.py b/certbot/certbot/crypto_util.py
index e6c063eed..2618a50e7 100644
--- a/certbot/certbot/crypto_util.py
+++ b/certbot/certbot/crypto_util.py
@@ -237,7 +237,15 @@ def load_cert(cert_path):
 
 
 def cert_sha1_fingerprint(cert_path):
-    """Get sha1 digest of the certificate fingerprint"""
+    """Read fingerprint of a certificate pointed by its file path
+    and returns sha1 digest of said fingerprint.
+
+    :param str cert_path: File path to the x509 certificate file
+
+    :returns: SHA-1 fingerprint of the certificate
+    :rtype: bytes
+    """
+
     cert = load_cert(cert_path)
     return cert.fingerprint(hashes.SHA1())
 
diff --git a/certbot/certbot/plugins/enhancements.py b/certbot/certbot/plugins/enhancements.py
index ccfc03cee..e9e98d16d 100644
--- a/certbot/certbot/plugins/enhancements.py
+++ b/certbot/certbot/plugins/enhancements.py
@@ -170,6 +170,7 @@ class OCSPPrefetchEnhancement(object):
     Methods:
         enable_ocsp_prefetch is called when the domain is configured to
         serve OCSP responses using mechanism called OCSP Stapling.
+
         update_ocsp_prefetch is called every time when Certbot is run using 'renew'
         verb. Certbot should proceed to make a request to the OCSP server in order
         to fetch an OCSP response and to store the recieved response, if valid.