Now that 3.7 is the oldest supported Python, let's move to f-strings.

Author: mikeckennedy

src/04-asyncio/loops/loops_asyncio/loop_program.py

@@ -5,7 +5,7 @@
 
 def main():
     lim = 250_000
-    print("Running standard loop with {:,} actions.".format(lim*2))
+    print(f"Running standard loop with {lim * 2:,} actions.")
     t0 = datetime.datetime.now()
 
     # Changed this from the video due to changes in Python 3.10:
@@ -22,7 +22,7 @@ def main():
     loop.run_until_complete(final_task)
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 async def generate_data(num: int, data: asyncio.Queue):

src/04-asyncio/loops/loops_uv/loop_program_uv.py

@@ -8,7 +8,7 @@
 
 def main():
     lim = 250000
-    print("Running standard loop with {:,} actions.".format(lim * 2))
+    print(f"Running standard loop with {lim * 2:,} actions.")
     t0 = datetime.datetime.now()
 
     # Changed this from the video due to changes in Python 3.10:
@@ -24,7 +24,7 @@ def main():
     loop.run_until_complete(final_task)
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 async def generate_data(num: int, data: asyncio.Queue):

src/04-asyncio/producer_consumer/prod_async/async_program.py

@@ -22,15 +22,15 @@ def main():
     loop.run_until_complete(final_task)
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 async def generate_data(num: int, data: asyncio.Queue):
     for idx in range(1, num + 1):
         item = idx*idx
         await data.put((item, datetime.datetime.now()))
 
-        print(colorama.Fore.YELLOW + " -- generated item {}".format(idx), flush=True)
+        print(colorama.Fore.YELLOW + f" -- generated item {idx}", flush=True)
         await asyncio.sleep(random.random() + .5)
 
 
@@ -45,7 +45,7 @@ async def process_data(num: int, data: asyncio.Queue):
         dt = datetime.datetime.now() - t
 
         print(colorama.Fore.CYAN +
-              " +++ Processed value {} after {:,.2f} sec.".format(value, dt.total_seconds()), flush=True)
+              f" +++ Processed value {value} after {dt.total_seconds():,.2f} sec.", flush=True)
         await asyncio.sleep(.5)
 
 

src/04-asyncio/producer_consumer/prod_sync/sync_program.py

@@ -12,15 +12,15 @@ def main():
     process_data(20, data)
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 def generate_data(num: int, data: list):
     for idx in range(1, num + 1):
         item = idx*idx
         data.append((item, datetime.datetime.now()))
 
-        print(colorama.Fore.YELLOW + " -- generated item {}".format(idx), flush=True)
+        print(colorama.Fore.YELLOW + f" -- generated item {idx}", flush=True)
         time.sleep(random.random() + .5)
 
 
@@ -38,7 +38,7 @@ def process_data(num: int, data: list):
         dt = datetime.datetime.now() - t
 
         print(colorama.Fore.CYAN +
-              " +++ Processed value {} after {:,.2f} sec.".format(value, dt.total_seconds()), flush=True)
+              f" +++ Processed value {value} after {dt.total_seconds():,.2f} sec.", flush=True)
         time.sleep(.5)
 
 

src/05-threads/basic_threads/sync_prod.py

@@ -14,7 +14,7 @@ def main():
     process_data(40, data)
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 def generate_data(num: int, data: list):
@@ -40,7 +40,7 @@ def process_data(num: int, data: list):
         dt = datetime.datetime.now() - t
 
         print(colorama.Fore.CYAN +
-              " +++ Processed value {} after {:,.2f} sec.".format(value, dt.total_seconds()), flush=True)
+              f" +++ Processed value {value} after {dt.total_seconds():,.2f} sec.", flush=True)
         time.sleep(.5)
 
 

src/05-threads/basic_threads/threaded_prod.py

@@ -28,7 +28,7 @@ def main():
             break
 
     dt = datetime.datetime.now() - t0
-    print(colorama.Fore.WHITE + "App exiting, total time: {:,.2f} sec.".format(dt.total_seconds()), flush=True)
+    print(colorama.Fore.WHITE + f"App exiting, total time: {dt.total_seconds():,.2f} sec.", flush=True)
 
 
 def check_cancel():
@@ -62,7 +62,7 @@ def process_data(num: int, data: list):
         dt = datetime.datetime.now() - t
 
         print(colorama.Fore.CYAN +
-              " +++ Processed value {} after {:,.2f} sec.".format(value, dt.total_seconds()), flush=True)
+              f" +++ Processed value {value} after {dt.total_seconds():,.2f} sec.", flush=True)
         time.sleep(.5)
 
 

src/05-threads/cpu_attempt/compute_it.py

@@ -10,7 +10,7 @@ def main():
     do_math(num=30000000)
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
 
 
 def do_math(start=0, num=10):

src/05-threads/cpu_attempt/compute_threaded.py

@@ -10,7 +10,7 @@ def main():
     t0 = datetime.datetime.now()
 
     # do_math(num=30000000)
-    print("Doing math on {:,} processors.".format(multiprocessing.cpu_count()))
+    print(f"Doing math on {multiprocessing.cpu_count():,} processors.")
 
     processor_count = multiprocessing.cpu_count()
     threads = []
@@ -25,7 +25,7 @@ def main():
     [t.join() for t in threads]
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
 
 
 def do_math(start=0, num=10):

src/05-threads/hello_threads/hello.py

@@ -22,7 +22,7 @@ def main():
 
 def greeter(name: str, times: int):
     for n in range(0, times):
-        print("{}. Hello there {}".format(n, name))
+        print(f"{n}. Hello there {name}")
         time.sleep(1)
 
 

src/06-thread-safety/safe_bank.py

@@ -32,7 +32,7 @@ def main():
 
     dt = datetime.datetime.now() - t0
 
-    print("Transfers complete ({:,.2f}) sec".format(dt.total_seconds()))
+    print(f"Transfers complete ({dt.total_seconds():,.2f}) sec")
     validate_bank(accounts, total)
 
 
@@ -87,8 +87,7 @@ def validate_bank(accounts: List[Account], total: int, quiet=False):
             current, total
         ), flush=True)
     elif not quiet:
-        print("All good: Consistent account balance: ${:,}".format(
-            total), flush=True)
+        print(f"All good: Consistent account balance: ${total:,}", flush=True)
 
 
 def get_two_accounts(accounts):

src/06-thread-safety/safe_bank_fine_grained.py

@@ -33,7 +33,7 @@ def main():
 
     dt = datetime.datetime.now() - t0
 
-    print("Transfers complete ({:,.2f}) sec".format(dt.total_seconds()))
+    print(f"Transfers complete ({dt.total_seconds():,.2f}) sec")
     validate_bank(accounts, total)
 
 
@@ -100,8 +100,7 @@ def validate_bank(accounts: List[Account], total: int, quiet=False):
             current, total
         ), flush=True)
     elif not quiet:
-        print("All good: Consistent account balance: ${:,}".format(
-            total), flush=True)
+        print(f"All good: Consistent account balance: ${total:,}", flush=True)
 
 
 def get_two_accounts(accounts):

src/06-thread-safety/unsafe_bank.py

@@ -32,7 +32,7 @@ def main():
 
     dt = datetime.datetime.now() - t0
 
-    print("Transfers complete ({:,.2f}) sec".format(dt.total_seconds()))
+    print(f"Transfers complete ({dt.total_seconds():,.2f}) sec")
     validate_bank(accounts, total)
 
 
@@ -71,8 +71,7 @@ def validate_bank(accounts: List[Account], total: int, quiet=False):
             current, total
         ), flush=True)
     elif not quiet:
-        print("All good: Consistent account balance: ${:,}".format(
-            total), flush=True)
+        print(f"All good: Consistent account balance: ${total:,}", flush=True)
 
 
 def get_two_accounts(accounts):

src/07-multiprocessing/cpu_attempt/compute_it.py

@@ -10,7 +10,7 @@ def main():
     do_math(num=30000000)
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
 
 
 def do_math(start=0, num=10):

src/07-multiprocessing/cpu_attempt/compute_multiprocessing.py

@@ -8,7 +8,7 @@ def main():
 
     t0 = datetime.datetime.now()
 
-    print("Doing math on {:,} processors.".format(multiprocessing.cpu_count()))
+    print(f"Doing math on {multiprocessing.cpu_count():,} processors.")
 
     pool = multiprocessing.Pool()
     processor_count = multiprocessing.cpu_count()
@@ -22,7 +22,7 @@ def main():
     pool.join()
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
     print("Our results: ")
     for t in tasks:
         print(t.get())

src/07-multiprocessing/cpu_attempt/compute_threaded.py

@@ -10,7 +10,7 @@ def main():
     t0 = datetime.datetime.now()
 
     # do_math(num=30000000)
-    print("Doing math on {:,} processors.".format(multiprocessing.cpu_count()))
+    print(f"Doing math on {multiprocessing.cpu_count():,} processors.")
 
     processor_count = multiprocessing.cpu_count()
     threads = []
@@ -25,7 +25,7 @@ def main():
     [t.join() for t in threads]
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
 
 
 def do_math(start=0, num=10):

src/08-execution-pools/program.py

@@ -29,7 +29,7 @@ def main():
 
     print("Done", flush=True)
     for f in work:
-        print("{}".format(f.result()), flush=True)
+        print(f"{f.result()}", flush=True)
 
 
 def get_title(url: str) -> str:

src/09-built-on-asyncio/the_unsync/nosync.py

@@ -20,7 +20,7 @@ def main():
     wait_some()
 
     dt = datetime.datetime.now() - t0
-    print("Synchronous version done in {:,.2f} seconds.".format(dt.total_seconds()))
+    print(f"Synchronous version done in {dt.total_seconds():,.2f} seconds.")
 
 
 def compute_some():
@@ -37,7 +37,7 @@ def download_some():
 
     text = resp.text
 
-    print("Downloaded (more) {:,} characters.".format(len(text)))
+    print(f"Downloaded (more) {len(text):,} characters.")
 
 
 def download_some_more():
@@ -48,7 +48,7 @@ def download_some_more():
 
     text = resp.text
 
-    print("Downloaded {:,} characters.".format(len(text)))
+    print(f"Downloaded {len(text):,} characters.")
 
 
 def wait_some():

src/09-built-on-asyncio/the_unsync/presync.py

@@ -30,7 +30,7 @@ def main():
     loop.run_until_complete(asyncio.gather(*tasks))
 
     dt = datetime.datetime.now() - t0
-    print("Synchronous version done in {:,.2f} seconds.".format(dt.total_seconds()))
+    print(f"Synchronous version done in {dt.total_seconds():,.2f} seconds.")
 
 
 async def compute_some():
@@ -48,7 +48,7 @@ async def download_some():
 
             text = await resp.text()
 
-    print("Downloaded (more) {:,} characters.".format(len(text)))
+    print(f"Downloaded (more) {len(text):,} characters.")
 
 
 async def download_some_more():
@@ -59,7 +59,7 @@ async def download_some_more():
 
     text = resp.text
 
-    print("Downloaded {:,} characters.".format(len(text)))
+    print(f"Downloaded {len(text):,} characters.")
 
 
 async def wait_some():

src/09-built-on-asyncio/the_unsync/thesync.py

@@ -27,7 +27,7 @@ def main():
     [t.result() for t in tasks]
 
     dt = datetime.datetime.now() - t0
-    print("Synchronous version done in {:,.2f} seconds.".format(dt.total_seconds()))
+    print(f"Synchronous version done in {dt.total_seconds():,.2f} seconds.")
 
 
 @unsync(cpu_bound=True)
@@ -47,7 +47,7 @@ async def download_some():
 
             text = await resp.text()
 
-    print("Downloaded (more) {:,} characters.".format(len(text)))
+    print(f"Downloaded (more) {len(text):,} characters.")
 
 
 @unsync()
@@ -59,7 +59,7 @@ def download_some_more():
 
     text = resp.text
 
-    print("Downloaded {:,} characters.".format(len(text)))
+    print(f"Downloaded {len(text):,} characters.")
 
 
 @unsync()

src/10-async-web/acityscape_api/app.py

@@ -21,7 +21,7 @@ def configure_app():
     services.sun_service.use_cached_data = data.get('use_cached_data')
     services.location_service.use_cached_data = data.get('use_cached_data')
 
-    print("Using cached data? {}".format(data.get('use_cached_data')))
+    print(f"Using cached data? {data.get('use_cached_data')}")
 
 
 def run_web_app():

src/10-async-web/cityscape_api/app.py

@@ -21,7 +21,7 @@ def configure_app():
     services.sun_service.use_cached_data = data.get('use_cached_data')
     services.location_service.use_cached_data = data.get('use_cached_data')
 
-    print("Using cached data? {}".format(data.get('use_cached_data')))
+    print(f"Using cached data? {data.get('use_cached_data')}")
 
 
 def run_web_app():

src/11-cython/perf/compute_cython.py

@@ -7,7 +7,7 @@
 def main():
     math_core.do_math(1)
 
-    print("Doing math on {:,} processors.".format(multiprocessing.cpu_count()))
+    print(f"Doing math on {multiprocessing.cpu_count():,} processors.")
 
     processor_count = multiprocessing.cpu_count()
     threads = []

src/11-cython/perf/compute_it.py

@@ -10,7 +10,7 @@ def main():
     do_math(num=3_000_000)
 
     dt = datetime.datetime.now() - t0
-    print("Done in {:,.2f} sec.".format(dt.total_seconds()))
+    print(f"Done in {dt.total_seconds():,.2f} sec.")
 
 
 def do_math(start=0, num=10):

src/11-cython/perf/compute_multiprocessing.py

@@ -8,7 +8,7 @@ def main():
 
     t0 = datetime.datetime.now()
 
-    print("Doing math on {:,} processors.".format(multiprocessing.cpu_count()))
+    print(f"Doing math on {multiprocessing.cpu_count():,} processors.")
 
     pool = multiprocessing.Pool()
     processor_count = multiprocessing.cpu_count()