diff --git a/news/toml.vendor.rst b/news/toml.vendor.rst
new file mode 100644
index 000000000..566c104f8
--- /dev/null
+++ b/news/toml.vendor.rst
@@ -0,0 +1 @@
+Upgrade toml to 0.10.2
diff --git a/src/pip/_vendor/toml/__init__.py b/src/pip/_vendor/toml/__init__.py
index 7a08fe725..34a5eabb6 100644
--- a/src/pip/_vendor/toml/__init__.py
+++ b/src/pip/_vendor/toml/__init__.py
@@ -6,7 +6,7 @@ Released under the MIT license.
 from pip._vendor.toml import encoder
 from pip._vendor.toml import decoder
 
-__version__ = "0.10.1"
+__version__ = "0.10.2"
 _spec_ = "0.5.0"
 
 load = decoder.load
diff --git a/src/pip/_vendor/toml/common.py b/src/pip/_vendor/toml/common.py
deleted file mode 100644
index a5d673dac..000000000
--- a/src/pip/_vendor/toml/common.py
+++ /dev/null
@@ -1,6 +0,0 @@
-# content after the \
-escapes = ['0', 'b', 'f', 'n', 'r', 't', '"']
-# What it should be replaced by
-escapedchars = ['\0', '\b', '\f', '\n', '\r', '\t', '\"']
-# Used for substitution
-escape_to_escapedchars = dict(zip(_escapes, _escapedchars))
diff --git a/src/pip/_vendor/toml/decoder.py b/src/pip/_vendor/toml/decoder.py
index e4887770c..e071100de 100644
--- a/src/pip/_vendor/toml/decoder.py
+++ b/src/pip/_vendor/toml/decoder.py
@@ -440,7 +440,8 @@ def loads(s, _dict=dict, decoder=None):
                                            groups[i][0] == "'"):
                     groupstr = groups[i]
                     j = i + 1
-                    while not groupstr[0] == groupstr[-1]:
+                    while ((not groupstr[0] == groupstr[-1]) or
+                           len(groupstr) == 1):
                         j += 1
                         if j > len(groups) + 2:
                             raise TomlDecodeError("Invalid group name '" +
@@ -811,8 +812,12 @@ class TomlDecoder(object):
             raise ValueError("Empty value is invalid")
         if v == 'true':
             return (True, "bool")
+        elif v.lower() == 'true':
+            raise ValueError("Only all lowercase booleans allowed")
         elif v == 'false':
             return (False, "bool")
+        elif v.lower() == 'false':
+            raise ValueError("Only all lowercase booleans allowed")
         elif v[0] == '"' or v[0] == "'":
             quotechar = v[0]
             testv = v[1:].split(quotechar)
diff --git a/src/pip/_vendor/toml/encoder.py b/src/pip/_vendor/toml/encoder.py
index a8b03c7be..7fb94da98 100644
--- a/src/pip/_vendor/toml/encoder.py
+++ b/src/pip/_vendor/toml/encoder.py
@@ -61,7 +61,7 @@ def dumps(o, encoder=None):
     retval += addtoretval
     outer_objs = [id(o)]
     while sections:
-        section_ids = [id(section) for section in sections]
+        section_ids = [id(section) for section in sections.values()]
         for outer_obj in outer_objs:
             if outer_obj in section_ids:
                 raise ValueError("Circular reference detected")
diff --git a/src/pip/_vendor/toml/tz.py b/src/pip/_vendor/toml/tz.py
index 93c3c8ad2..bf20593a2 100644
--- a/src/pip/_vendor/toml/tz.py
+++ b/src/pip/_vendor/toml/tz.py
@@ -11,6 +11,9 @@ class TomlTz(tzinfo):
         self._hours = int(self._raw_offset[1:3])
         self._minutes = int(self._raw_offset[4:6])
 
+    def __deepcopy__(self, memo):
+        return self.__class__(self._raw_offset)
+
     def tzname(self, dt):
         return "UTC" + self._raw_offset
 
diff --git a/src/pip/_vendor/vendor.txt b/src/pip/_vendor/vendor.txt
index 468107bb6..21614a5e6 100644
--- a/src/pip/_vendor/vendor.txt
+++ b/src/pip/_vendor/vendor.txt
@@ -20,5 +20,5 @@ resolvelib==0.5.2
 retrying==1.3.3
 setuptools==44.0.0
 six==1.15.0
-toml==0.10.1
+toml==0.10.2
 webencodings==0.5.1