Merge branch 'master' into python-download-file-from-url

KateFinegan · web-flow · commit 86d74058c73a · 2023-07-18T16:37:17.000-06:00
diff --git a/ipython-console/README.md b/ipython-console/README.md
@@ -0,0 +1,3 @@
+# Code Snippets and IPython Cheat Sheet
+
+This folder contains code resources and an IPython magic command cheat sheet based on the content of the Real Python tutorial [Unlock IPython's Magical Toolbox for Your Coding Journey](https://realpython.com/ipython-interactive-python-shell/).
diff --git a/ipython-console/employee.py b/ipython-console/employee.py
@@ -0,0 +1,4 @@
+first_name = "Han"
+last_name = "Solo"
+department = "Accounts"
+salary = 1000
diff --git a/ipython-console/employee_embedded.py b/ipython-console/employee_embedded.py
@@ -0,0 +1,10 @@
+import IPython
+
+first_name = "Han"
+last_name = "Solo"
+department = "Accounts"
+print(f"{first_name} {last_name}")
+
+IPython.embed()
+
+salary = 1000
diff --git a/ipython-console/increment.py b/ipython-console/increment.py
@@ -0,0 +1,12 @@
+def salary_increment(salary):
+    """Calculate the new salary after applying an increment.
+
+    Args:
+        salary (int): The current salary.
+
+    Returns:
+        str: A string indicating the new salary after increment.
+    """
+    increment = salary / 10
+    new_salary = increment + salary
+    return f"Your New Salary is: {new_salary}"
diff --git a/ipython-console/ipython-cheat-sheet.pdf b/ipython-console/ipython-cheat-sheet.pdf
diff --git a/python-312/README.md b/python-312/README.md
@@ -14,6 +14,7 @@ You can learn more about Python 3.12's new features in the following Real Python
 
 - [Python 3.12 Preview: Ever Better Error Messages](https://realpython.com/python312-error-messages/)
 - [Python 3.12 Preview: Support For the Linux `perf` Profiler](https://realpython.com/python312-perf-profiler/)
+- [Python 3.12 Preview: More Intuitive and Consistent F-Strings](https://realpython.com/python312-f-strings/)
 
 You'll find examples from all these tutorials in this repository.
 
@@ -117,6 +118,24 @@ $ cat traces_censored.txt | flamegraph.pl --minwidth 10 > flamegraph.svg
 
 See [Support For the Linux `perf` Profiler in Python 3.12](https://realpython.com/python312-perf-profiler/) for more information.
 
+### New F-String Implementation and Syntax Formalization
+
+Once you have 3.12 installed, open any file from the `f-string/` folder. Uncomment the code as needed. [Run the scripts](https://realpython.com/run-python-scripts/) from your command line or execute the code directly in a [REPL](https://realpython.com/python-repl/) session. You'll see the new f-string implementation in action.
+
+For example, go ahead and run the following command:
+
+```console
+$ python backslashes.py
+Hello
+World!
+I
+am
+a
+Pythonista!
+```
+
+In this example, you can see how the new implementation of f-strings allows you to include backslashes in embedded expressions. This wasn't possible with f-strings in earlier versions of Python. 
+
 ## Authors
 
 - **Martin Breuss**, E-mail: [martin@realpython.com](martin@realpython.com)
diff --git a/python-312/f-string/backslashes.py b/python-312/f-string/backslashes.py
@@ -0,0 +1,4 @@
+words = ["Hello", "World!", "I", "am", "a", "Pythonista!"]
+
+# Uncomment the following line and run it in Python 3.12
+# print(f"{'\n'.join(words)}")
diff --git a/python-312/f-string/comments.py b/python-312/f-string/comments.py
@@ -0,0 +1,10 @@
+employee = {
+    "name": "John Doe",
+    "age": 35,
+    "job": "Python Developer",
+}
+
+# Uncomment the following code and run it in Python 3.12
+# f"""Storing employee's data: {
+#     employee['name'].upper()  # Always uppercase name before storing
+# }"""
diff --git a/python-312/f-string/nested.py b/python-312/f-string/nested.py
@@ -0,0 +1,13 @@
+# Uncomment the following code and run it in Python 3.12
+
+# f"{
+#     f"{
+#         f"{
+#             f"{
+#                 f"{
+#                     f"Deeply nested f-string!"
+#                 }"
+#             }"
+#         }"
+#     }"
+# }"
diff --git a/python-312/f-string/quotes.py b/python-312/f-string/quotes.py
@@ -0,0 +1,8 @@
+employee = {
+    "name": "John Doe",
+    "age": 35,
+    "job": "Python Developer",
+}
+
+# Uncomment the following line and run it in Python 3.12
+# f"Employee: {employee["name"]}"
diff --git a/python-312/perf-profiler/benchmark_optimized.py b/python-312/perf-profiler/benchmark_optimized.py
@@ -31,8 +31,8 @@ def get_average_luminance(pixels):
     return exp(mean([log(luminance(pixel) + 1e-9) for pixel in pixels]))
 
 
-def mean(n):
-    return sum(n) / len(n)
+def mean(numbers):
+    return sum(numbers) / len(numbers)
 
 
 def luminance(pixel):
diff --git a/python-list/README.md b/python-list/README.md
@@ -0,0 +1,3 @@
+# Python's list Data Type: A Deep Dive With Examples
+
+This folder provides the code examples for the Real Python tutorial [Python's `list` Data Type: A Deep Dive With Examples](https://realpython.com/python-list/).
diff --git a/python-list/chunks.py b/python-list/chunks.py
@@ -0,0 +1,6 @@
+def split_list(list_object, chunk_size):
+    chunks = []
+    for start in range(0, len(list_object), chunk_size):
+        stop = start + chunk_size
+        chunks.append(list_object[start:stop])
+    return chunks
diff --git a/python-list/employee.py b/python-list/employee.py
@@ -0,0 +1,10 @@
+employees = [
+    ("John", 30, "Designer", 75000),
+    ("Jane", 28, "Engineer", 60000),
+    ("Bob", 35, "Analyst", 50000),
+    ("Mary", 25, "Service", 40000),
+    ("Tom", 40, "Director", 90000),
+]
+
+
+sorted_employees = sorted(employees, key=lambda e: e[1])
diff --git a/python-list/fibonacci.py b/python-list/fibonacci.py
@@ -0,0 +1,6 @@
+def fibonacci_generator(stop):
+    current_fib, next_fib = 0, 1
+    for _ in range(0, stop):
+        fib_number = current_fib
+        current_fib, next_fib = next_fib, current_fib + next_fib
+        yield fib_number
diff --git a/python-list/grades.py b/python-list/grades.py
@@ -0,0 +1,39 @@
+class GradeList(list):
+    def __init__(self, grades):
+        grades = [self._validate(grade) for grade in grades]
+        super().__init__(grades)
+
+    def __setitem__(self, index, grade):
+        if isinstance(index, slice):
+            start, stop, step = index.indices(len(self))
+            grades = [self._validate(grade) for grade in grade]
+            return super().__setitem__(slice(start, stop, step), grades)
+        super().__setitem__(index, self._validate(grade))
+
+    def __add__(self, grades):
+        grades = [self._validate(grade) for grade in grades]
+        grades = super().__add__(grades)
+        return self.__class__(grades)
+
+    __radd__ = __add__
+
+    def __iadd__(self, grades):
+        grades = [self._validate(grade) for grade in grades]
+        return super().__iadd__(grades)
+
+    def append(self, grade):
+        return super().append(self._validate(grade))
+
+    def extend(self, grades):
+        grades = [self._validate(grade) for grade in grades]
+        return super().extend(grades)
+
+    def average(self):
+        return sum(self) / len(self)
+
+    def _validate(self, value):
+        if not isinstance(value, (int, float)):
+            raise TypeError("grades must be numeric")
+        if not (0 <= value <= 100):
+            raise ValueError("grade must be between 0 and 100")
+        return value
diff --git a/python-list/matrix.py b/python-list/matrix.py
@@ -0,0 +1,9 @@
+matrix = []
+for row in range(5):
+    matrix.append([])
+    for _ in range(5):
+        matrix[row].append(0)
+
+matrix = [[0 for _ in range(5)] for _ in range(5)]
+
+matrix = [[0] * 5 for _ in range(5)]
diff --git a/python-list/median.py b/python-list/median.py
@@ -0,0 +1,10 @@
+def median(samples):
+    n = len(samples)
+    middle_index = n // 2
+    sorted_samples = sorted(samples)
+    # Odd number of values
+    if n % 2:
+        return sorted_samples[middle_index]
+    # Even number of values
+    lower, upper = middle_index - 1, middle_index + 1
+    return sum(sorted_samples[lower:upper]) / 2
diff --git a/python-list/repeated.py b/python-list/repeated.py
@@ -0,0 +1,18 @@
+def get_unique_items(list_object):
+    result = []
+    for item in list_object:
+        if item not in result:
+            result.append(item)
+    return result
+
+
+# Faster but requires more memory:
+#
+# def get_unique_items(list_object):
+#     result = []
+#     unique_items = set()
+#     for item in list_object:
+#         if item not in unique_items:
+#             result.append(item)
+#             unique_items.add(item)
+#     return result
diff --git a/python-profiling/README.md b/python-profiling/README.md
@@ -0,0 +1,111 @@
+# Profiling in Python: How to Find Performance Bottlenecks
+
+This folder holds sample code that supplements the Real Python tutorial [Profiling in Python: How to Find Performance Bottlenecks](https://realpython.com/python-profiling/).
+
+## Profiler 1: `time`
+
+```shell
+$ python profile_time.py 
+sleeper()
+ Real time: 1.75 seconds
+ CPU time: 0.00 seconds
+
+spinlock()
+ Real time: 1.80 seconds
+ CPU time: 1.80 seconds
+```
+
+## Profiler 2: `timeit`
+
+```shell
+$ python profile_timeit.py 
+Average time is 0.15 seconds
+```
+
+## Profiler 3: `cProfile`
+
+```shell
+$ python profile_cprofile.py 
+fib(35) = 9227465
+         29860712 function calls (10 primitive calls) in 9.487 seconds
+
+   Ordered by: call count
+
+   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
+29860703/1    9.487    0.000    9.487    9.487 profile_cprofile.py:5(fib)
+        1    0.000    0.000    0.000    0.000 pstats.py:118(init)
+        1    0.000    0.000    0.000    0.000 pstats.py:137(load_stats)
+        1    0.000    0.000    0.000    0.000 pstats.py:108(__init__)
+        1    0.000    0.000    0.000    0.000 cProfile.py:51(create_stats)
+        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
+        1    0.000    0.000    0.000    0.000 {built-in method builtins.hasattr}
+        1    0.000    0.000    0.000    0.000 {built-in method builtins.isinstance}
+        1    0.000    0.000    0.000    0.000 {built-in method builtins.len}
+        1    0.000    0.000    0.000    0.000 {built-in method builtins.print}
+```
+
+## Profiler 4: `pyinstrument`
+
+Make sure to install the third-party library [`pyinstrument`](https://pypi.org/project/pyinstrument/) from the supplied `requirements.txt` file into a virtual environment first:
+
+```shell
+$ python3 -m venv venv/
+$ source venv/bin/activate
+(venv) $ python -m pip install -r requirements.txt
+```
+
+Then, you can run the sample script while you're still in the same virtual environment:
+
+```shell
+(venv) $ python profile_pyinstrument.py 
+n = 10         [2.8, 2.8, 2.8, 3.2, 2.4]
+n = 100        [3.04, 3.28, 3.24, 2.92, 3.24]
+n = 1,000      [3.176, 3.192, 3.188, 3.076, 3.132]
+n = 10,000     [3.1376, 3.1328, 3.172, 3.1292, 3.1376]
+n = 100,000    [3.14636, 3.13424, 3.15104, 3.14212, 3.14612]
+n = 1,000,000  [3.141736, 3.141708, 3.14168, 3.141828, 3.140708]
+n = 10,000,000 [3.14143, 3.1403824, 3.1411704, 3.1408808, 3.1420068]
+
+  _     ._   __/__   _ _  _  _ _/_   Recorded: 11:49:03  Samples:  243
+ /_//_/// /_\ / //_// / //_'/ //     Duration: 24.334    CPU time: 24.298
+/   _/                      v4.5.0
+
+Program: profile_pyinstrument.py
+
+24.300 <module>  profile_pyinstrument.py:1
+└─ 24.300 estimate_pi  profile_pyinstrument.py:6
+   ├─ 23.200 <genexpr>  profile_pyinstrument.py:7
+   │  ├─ 15.200 point  profile_pyinstrument.py:14
+   │  │  ├─ 7.700 Random.uniform  random.py:520
+   │  │  │     [4 frames hidden]  random, <built-in>
+   │  │  │        6.200 [self]  None
+   │  │  └─ 7.500 [self]  None
+   │  ├─ 4.600 [self]  None
+   │  └─ 3.400 hits  profile_pyinstrument.py:10
+   │     ├─ 2.400 [self]  None
+   │     └─ 1.000 abs  None
+   │           [2 frames hidden]  <built-in>
+   └─ 1.100 [self]  None
+```
+
+## Profiler 5: `perf`
+
+Make sure to follow the setup instructions in the [Python 3.12 Preview: Support For the Linux perf Profiler](https://realpython.com/python312-perf-profiler/) tutorial.
+
+Next, record samples into a local binary file named `perf.data`:
+
+```shell
+$ sudo perf record -g -F 999 $HOME/python-custom-build/bin/python3 -X perf profile_perf.py
+```
+
+Finally, display a report by issuing the following command while you're in the same folder:
+
+```shell
+$ sudo perf report
+```
+
+For an alternative view, try this instead:
+
+```shell
+$ sudo perf report --hierarchy --sort comm,dso,sample
+```
diff --git a/python-profiling/profile_cprofile.py b/python-profiling/profile_cprofile.py
@@ -0,0 +1,11 @@
+from cProfile import Profile
+from pstats import SortKey, Stats
+
+
+def fib(n):
+    return n if n < 2 else fib(n - 2) + fib(n - 1)
+
+
+with Profile() as profile:
+    print(f"{fib(35) = }")
+    Stats(profile).strip_dirs().sort_stats(SortKey.CALLS).print_stats()
diff --git a/python-profiling/profile_perf.py b/python-profiling/profile_perf.py
@@ -0,0 +1,33 @@
+from concurrent.futures import ThreadPoolExecutor
+
+
+def find_divisors(n):
+    return [i for i in range(1, n + 1) if n % i == 0]
+
+
+def slow_function():
+    print("Slow thread started")
+    try:
+        return find_divisors(100_000_000)
+    finally:
+        print("Slow thread ended")
+
+
+def fast_function():
+    print("Fast thread started")
+    try:
+        return find_divisors(50_000_000)
+    finally:
+        print("Fast thread ended")
+
+
+def main():
+    with ThreadPoolExecutor(max_workers=2) as pool:
+        pool.submit(slow_function)
+        pool.submit(fast_function)
+
+    print("Main thread ended")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/python-profiling/profile_pyinstrument.py b/python-profiling/profile_pyinstrument.py
diff --git a/python-profiling/profile_time.py b/python-profiling/profile_time.py
diff --git a/python-profiling/profile_timeit.py b/python-profiling/profile_timeit.py
diff --git a/python-profiling/requirements.txt b/python-profiling/requirements.txt
diff --git a/python-rounding/README.md b/python-rounding/README.md
diff --git a/python-rounding/rounding.py b/python-rounding/rounding.py
diff --git a/python-rounding/rounding_numpy.py b/python-rounding/rounding_numpy.py

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+# Code Snippets and IPython Cheat Sheet`
	`2`	`+`
	`3`	`+This folder contains code resources and an IPython magic command cheat sheet based on the content of the Real Python tutorial [Unlock IPython's Magical Toolbox for Your Coding Journey](https://realpython.com/ipython-interactive-python-shell/).`
-Original file line number
+Diff line change
@@ @@ -0,0 +1,13 @@ @@
 +# Uncomment the following code and run it in Python 3.12
++
 +# f"{
 +#     f"{
 +#         f"{
 +#             f"{
 +#                 f"{
 +#                     f"Deeply nested f-string!"
 +#                 }"
 +#             }"
 +#         }"
 +#     }"
 +# }"