diff --git a/misc/format_server.py b/misc/format_server.py
index 5acb17e46b7edb..a73e5bbc8bdba8 100644
--- a/misc/format_server.py
+++ b/misc/format_server.py
@@ -75,7 +75,7 @@ def do_GET(self):
 
     # self.exec(f'git checkout master')
     def x():
-      a =    1
+      a = 1
 
 
 def run(addr, port):
diff --git a/python/taichi/core/util.py b/python/taichi/core/util.py
index 76a4576665f58d..53ee655e9b85f3 100644
--- a/python/taichi/core/util.py
+++ b/python/taichi/core/util.py
@@ -31,7 +31,9 @@ def import_tc_core(tmp_dir=None):
     import taichi_core as core
   except Exception as e:
     if isinstance(e, ImportError):
-      print("Share object taichi_core import failed. If you are on Windows, please consider installing \"Microsoft Visual C++ Redistributable\" (https://aka.ms/vs/16/release/vc_redist.x64.exe)")
+      print(
+          "Share object taichi_core import failed. If you are on Windows, please consider installing \"Microsoft Visual C++ Redistributable\" (https://aka.ms/vs/16/release/vc_redist.x64.exe)"
+      )
     raise e
   tc_core = core
   if get_os_name() != 'win':
@@ -127,6 +129,7 @@ def format(all=False, diff=None):
 
 create_sand_box_on_windows = True
 
+
 def build():
   tmp_cwd = os.getcwd()
   bin_dir = get_build_directory()
@@ -151,6 +154,7 @@ def build():
 
   os.chdir(tmp_cwd)
 
+
 def prepare_sandbox(src):
   global g_tmp_dir
   assert os.path.exists(src)
@@ -258,6 +262,7 @@ def prepare_sandbox(src):
 if log_level:
   tc_core.set_logging_level(log_level)
 
+
 def get_dll_name(name):
   if get_os_name() == 'linux':
     return 'libtaichi_%s.so' % name
@@ -295,7 +300,7 @@ def at_startup():
     if not os.path.exists(output_dir):
       print('Making output directory')
       os.mkdir(output_dir)
-      
+
   tc_core.set_core_state_python_imported(True)
 
 
@@ -321,26 +326,32 @@ def task():
 
   proc = multiprocessing.Process(target=task, daemon=True)
   proc.start()
-  
+
+
 def require_version(major, minor=None, patch=None):
   versions = [
-    int(tc_core.get_version_major()),
-    int(tc_core.get_version_minor()),
-    int(tc_core.get_version_patch()),
+      int(tc_core.get_version_major()),
+      int(tc_core.get_version_minor()),
+      int(tc_core.get_version_patch()),
   ]
-  match = major == versions[0] and (minor < versions[1] or minor == versions[1] and patch <= versions[2])
+  match = major == versions[0] and (
+      minor < versions[1] or minor == versions[1] and patch <= versions[2])
   if match:
     return
   else:
-    print("Taichi version mismatch. required >= {}.{}.{}".format(major, minor, patch))
+    print("Taichi version mismatch. required >= {}.{}.{}".format(
+        major, minor, patch))
     print("Installed =", tc_core.get_version_string())
     raise Exception("Taichi version mismatch")
 
+
 at_startup()
 
 device_string = 'cpu only' if not tc_core.with_cuda() else 'cuda {}'.format(
     tc_core.cuda_version())
-print(f'[Taichi] version {tc_core.get_version_string()}, {device_string}, commit {tc_core.get_commit_hash()[:8]}, python {sys.version_info[0]}.{sys.version_info[1]}.{sys.version_info[2]}')
+print(
+    f'[Taichi] version {tc_core.get_version_string()}, {device_string}, commit {tc_core.get_commit_hash()[:8]}, python {sys.version_info[0]}.{sys.version_info[1]}.{sys.version_info[2]}'
+)
 
 if not is_release():
   tc_core.set_core_trigger_gdb_when_crash(True)
diff --git a/python/taichi/main.py b/python/taichi/main.py
index 485a91299f0015..515d932ae46d7e 100644
--- a/python/taichi/main.py
+++ b/python/taichi/main.py
@@ -32,16 +32,19 @@ def test_python(test_files=(), verbose=False):
   if verbose:
     args += ['-s']
   if len(test_files) == 0 or len(test_files) > 4:
-    if int(pytest.main([os.path.join(root_dir, 'misc/empty_pytest.py'), '-n1'])) == 0: # if pytest has xdist
+    if int(
+        pytest.main([os.path.join(root_dir, 'misc/empty_pytest.py'),
+                     '-n1'])) == 0:  # if pytest has xdist
       try:
         from multiprocessing import cpu_count
-        threads = min(8, cpu_count()) # To prevent running out of memory
+        threads = min(8, cpu_count())  # To prevent running out of memory
       except:
         threads = 2
       env_threads = os.environ.get('TI_TEST_THREADS', '')
       if env_threads:
         threads = int(env_threads)
-        print(f'Following TI_TEST_THREADS to use {threads} testing thread(s)...')
+        print(
+            f'Following TI_TEST_THREADS to use {threads} testing thread(s)...')
       print(f'Starting {threads} testing thread(s)...')
       if threads > 1:
         args += ['-n', str(threads)]
@@ -66,7 +69,8 @@ def main(debug=False):
   if 'TI_DEBUG' in os.environ:
     val = os.environ['TI_DEBUG']
     if val not in ['0', '1']:
-      raise ValueError("Environment variable TI_DEBUG can only have value 0 or 1.")
+      raise ValueError(
+          "Environment variable TI_DEBUG can only have value 0 or 1.")
   if debug:
     lines.append(u' *****************Debug Mode****************')
     os.environ['TI_DEBUG'] = '1'
@@ -150,7 +154,8 @@ def main(debug=False):
   elif mode == "interpolate":
     interpolate_frames('.')
   elif mode == "doc":
-    os.system('cd {}/docs && sphinx-build -b html . build'.format(ti.get_repo_directory()))
+    os.system('cd {}/docs && sphinx-build -b html . build'.format(
+        ti.get_repo_directory()))
   elif mode == "video":
     files = sorted(os.listdir('.'))
     files = list(filter(lambda x: x.endswith('.png'), files))
@@ -248,5 +253,6 @@ def main(debug=False):
 def main_debug():
   main(debug=True)
 
+
 if __name__ == '__main__':
   exit(main())