diff --git a/pipenv/resolver.py b/pipenv/resolver.py
index 501e0219..08c16e57 100644
--- a/pipenv/resolver.py
+++ b/pipenv/resolver.py
@@ -315,7 +315,7 @@ class Entry:
                 return "*"
             specifier = f"=={specifier}"
         elif specifier.startswith("==") and specifier.count("=") > 3:
-            specifier = "=={}".format(specifier.lstrip("="))
+            specifier = f"=={specifier.lstrip('=')}"
         return specifier
 
     @staticmethod
@@ -476,13 +476,8 @@ class Entry:
                 if self.project.s.is_verbose():
                     err.print(f"Tried constraint: {constraint!r}")
                 msg = (
-                    "Cannot resolve conflicting version {}{} while {}{} is "
-                    "locked.".format(
-                        self.name,
-                        constraint.specifier,
-                        self.name,
-                        self.updated_specifier,
-                    )
+                    f"Cannot resolve conflicting version {self.name}{constraint.specifier} "
+                    f"while {self.name}{self.updated_specifier} is locked."
                 )
                 raise DependencyConflict(msg)
         return True
@@ -495,14 +490,9 @@ class Entry:
                 from pipenv.exceptions import DependencyConflict
 
                 msg = (
-                    "Cannot resolve conflicting versions: (Root: {}) {}{} (Pipfile) "
-                    "Incompatible with {}{} (resolved)\n".format(
-                        self.name,
-                        parent.pipfile_name,
-                        parent.pipfile_entry.requirement.specifiers,
-                        parent.name,
-                        parent.updated_specifiers,
-                    )
+                    f"Cannot resolve conflicting versions: (Root: {self.name}) "
+                    f"{parent.pipfile_name}{parent.pipfile_entry.requirement.specifiers} (Pipfile) "
+                    f"Incompatible with {parent.name}{parent.updated_specifiers} (resolved)\n"
                 )
                 raise DependencyConflict(msg)
 
diff --git a/pipenv/utils/funktools.py b/pipenv/utils/funktools.py
index be40778e..3c8201d0 100644
--- a/pipenv/utils/funktools.py
+++ b/pipenv/utils/funktools.py
@@ -149,7 +149,7 @@ def _get_powershell_path():
     ]
     powershell_path = next(iter(_walk_for_powershell(pth) for pth in paths), None)
     if not powershell_path:
-        powershell_path = subprocess.run(["where", "powershell"])
+        powershell_path = subprocess.run(["where", "powershell"], check=False)
     if powershell_path.stdout:
         return powershell_path.stdout.strip()
 
@@ -165,7 +165,7 @@ def _get_sid_with_powershell():
         "-Command",
         "Invoke-Expression '[System.Security.Principal.WindowsIdentity]::GetCurrent().user | Write-Host'",
     ]
-    sid = subprocess.run(args, capture_output=True)
+    sid = subprocess.run(args, capture_output=True, check=False)
     return sid.stdout.strip()
 
 
@@ -289,6 +289,7 @@ def set_write_bit(fn: str) -> None:
                 # >>> sys.stdout.encoding
                 # "UTF8"
                 encoding=locale.getpreferredencoding(),
+                check=False,
             )
             if not c.err and c.returncode == 0:
                 return
diff --git a/pipenv/utils/processes.py b/pipenv/utils/processes.py
index f061be50..9c0ea837 100644
--- a/pipenv/utils/processes.py
+++ b/pipenv/utils/processes.py
@@ -69,7 +69,9 @@ def subprocess_run(
         other_kwargs["stdout"] = subprocess.PIPE
         other_kwargs["stderr"] = subprocess.PIPE
     if block:
-        return subprocess.run(args, text=text, encoding=encoding, **other_kwargs)
+        return subprocess.run(
+            args, text=text, encoding=encoding, check=False, **other_kwargs
+        )
     else:
         return subprocess.Popen(
             args, universal_newlines=text, encoding=encoding, **other_kwargs
diff --git a/pipenv/utils/resolver.py b/pipenv/utils/resolver.py
index 97fa7883..49199422 100644
--- a/pipenv/utils/resolver.py
+++ b/pipenv/utils/resolver.py
@@ -144,8 +144,8 @@ class Resolver:
 
     def __repr__(self):
         return (
-            "<Resolver (constraints={self.initial_constraints}, req_dir={self.req_dir}, "
-            "sources={self.sources})>".format(self=self)
+            f"<Resolver (constraints={self.initial_constraints}, req_dir={self.req_dir}, "
+            f"sources={self.sources})>"
         )
 
     @staticmethod
diff --git a/pipenv/utils/toml.py b/pipenv/utils/toml.py
index e1261469..ddddc6c7 100644
--- a/pipenv/utils/toml.py
+++ b/pipenv/utils/toml.py
@@ -130,8 +130,7 @@ def tomlkit_dict_to_python(toml_dict):
         converted = toml_dict.copy()
     else:
         raise TypeError(
-            "Invalid type for conversion: expected Container, Dict, or Table, "
-            "got {!r}".format(toml_dict)
+            f"Invalid type for conversion: expected Container, Dict, or Table, got {toml_dict}"
         )
     if isinstance(converted, dict):
         return {k: tomlkit_value_to_python(v) for k, v in converted.items()}
diff --git a/tests/integration/conftest.py b/tests/integration/conftest.py
index 56d1ec71..51cfadbc 100644
--- a/tests/integration/conftest.py
+++ b/tests/integration/conftest.py
@@ -236,7 +236,7 @@ class _PipenvInstance:
         self._path = None
 
     def run_command(self, cmd):
-        result = subprocess.run(cmd, shell=True, capture_output=True)
+        result = subprocess.run(cmd, shell=True, capture_output=True, check=False)
         try:
             std_out_decoded = result.stdout.decode("utf-8")
         except UnicodeDecodeError:
diff --git a/tests/integration/test_install_categories.py b/tests/integration/test_install_categories.py
index 4fa39d77..6d52d680 100644
--- a/tests/integration/test_install_categories.py
+++ b/tests/integration/test_install_categories.py
@@ -1,5 +1,4 @@
 import os
-import tempfile
 
 import pytest
 
@@ -23,7 +22,7 @@ def test_basic_category_install_from_requirements(pipenv_instance_private_pypi):
     with pipenv_instance_private_pypi(pipfile=False) as p:
         # Write a requirements file
         with open("requirements.txt", "w") as f:
-            f.write(f"six==1.16.0")
+            f.write("six==1.16.0")
 
         c = p.pipenv("install --categories prereq")
         assert c.returncode == 0