diff --git a/docs/FAQ.md b/docs/FAQ.md
index b43101d1..782cb020 100644
--- a/docs/FAQ.md
+++ b/docs/FAQ.md
@@ -1 +1,14 @@
 # 常见问题
+
+## HTTPS SSLError
+
+请求 HTTPS 接口时，若本地开启了代理软件（Charles/Fiddler），由于 HTTPS 证书的原因，会导致 SSLError 的报错。
+
+解决的方式是，在 config 中增加 `verify: False`，原理见 requests 的 [`SSL Cert Verification`](https://requests.kennethreitz.org/en/master/user/advanced/#ssl-cert-verification) 部分。
+
+```yaml
+config:
+    name: XXX
+    base_url: XXX
+    verify: False
+```
diff --git a/httprunner/built_in.py b/httprunner/built_in.py
index 821304ca..43524d3f 100644
--- a/httprunner/built_in.py
+++ b/httprunner/built_in.py
@@ -30,6 +30,7 @@ def gen_random_string(str_len):
     return ''.join(
         random.choice(string.ascii_letters + string.digits) for _ in range(str_len))
 
+
 def get_timestamp(str_len=13):
     """ get timestamp string, length can only between 0 and 16
     """
@@ -38,12 +39,19 @@ def get_timestamp(str_len=13):
 
     raise ParamsError("timestamp length can only between 0 and 16.")
 
+
 def get_current_date(fmt="%Y-%m-%d"):
     """ get current date, default format is %Y-%m-%d
     """
     return datetime.datetime.now().strftime(fmt)
 
 
+def sleep(n_secs):
+    """ sleep n seconds
+    """
+    time.sleep(n_secs)
+
+
 ###############################################################################
 ##  upload files with requests-toolbelt
 #   e.g.
@@ -66,6 +74,7 @@ def get_current_date(fmt="%Y-%m-%d"):
 def multipart_encoder(**kwargs):
     """ initialize MultipartEncoder with uploading fields.
     """
+
     def get_filetype(file_path):
         file_type = filetype.guess(file_path)
         if file_type:
@@ -108,52 +117,66 @@ def multipart_content_type(multipart_encoder):
 def equals(check_value, expect_value):
     assert check_value == expect_value
 
+
 def less_than(check_value, expect_value):
     assert check_value < expect_value
 
+
 def less_than_or_equals(check_value, expect_value):
     assert check_value <= expect_value
 
+
 def greater_than(check_value, expect_value):
     assert check_value > expect_value
 
+
 def greater_than_or_equals(check_value, expect_value):
     assert check_value >= expect_value
 
+
 def not_equals(check_value, expect_value):
     assert check_value != expect_value
 
+
 def string_equals(check_value, expect_value):
     assert builtin_str(check_value) == builtin_str(expect_value)
 
+
 def length_equals(check_value, expect_value):
     assert isinstance(expect_value, integer_types)
     assert len(check_value) == expect_value
 
+
 def length_greater_than(check_value, expect_value):
     assert isinstance(expect_value, integer_types)
     assert len(check_value) > expect_value
 
+
 def length_greater_than_or_equals(check_value, expect_value):
     assert isinstance(expect_value, integer_types)
     assert len(check_value) >= expect_value
 
+
 def length_less_than(check_value, expect_value):
     assert isinstance(expect_value, integer_types)
     assert len(check_value) < expect_value
 
+
 def length_less_than_or_equals(check_value, expect_value):
     assert isinstance(expect_value, integer_types)
     assert len(check_value) <= expect_value
 
+
 def contains(check_value, expect_value):
     assert isinstance(check_value, (list, tuple, dict, basestring))
     assert expect_value in check_value
 
+
 def contained_by(check_value, expect_value):
     assert isinstance(expect_value, (list, tuple, dict, basestring))
     assert check_value in expect_value
 
+
 def type_match(check_value, expect_value):
     def get_type(name):
         if isinstance(name, type):
@@ -168,20 +191,16 @@ def type_match(check_value, expect_value):
 
     assert isinstance(check_value, get_type(expect_value))
 
+
 def regex_match(check_value, expect_value):
     assert isinstance(expect_value, basestring)
     assert isinstance(check_value, basestring)
     assert re.match(expect_value, check_value)
 
+
 def startswith(check_value, expect_value):
     assert builtin_str(check_value).startswith(builtin_str(expect_value))
 
+
 def endswith(check_value, expect_value):
     assert builtin_str(check_value).endswith(builtin_str(expect_value))
-
-""" built-in hooks
-"""
-def sleep_N_secs(n_secs):
-    """ sleep n seconds
-    """
-    time.sleep(n_secs)
diff --git a/tests/test_runner.py b/tests/test_runner.py
index df8c734d..2bc6fc8b 100644
--- a/tests/test_runner.py
+++ b/tests/test_runner.py
@@ -52,11 +52,11 @@ class TestRunner(ApiServerUnittest):
                     "name": "basic test with httpbin",
                     "base_url": HTTPBIN_SERVER,
                     "setup_hooks": [
-                        "${sleep_N_secs(0.5)}",
+                        "${sleep(0.5)}",
                         "${hook_print(setup)}"
                     ],
                     "teardown_hooks": [
-                        "${sleep_N_secs(1)}",
+                        "${sleep(1)}",
                         "${hook_print(teardown)}"
                     ]
                 },