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"2026-04-09T06:00:00+00:00" }, { "id": "01a0bba3-aedb-73e8-9010-139a05ce15d3", "title": "Timezone-aware datetime objects in Python with zoneinfo", "url": "https://lernerpython.com/2026/04/08/timezone-aware-datetime-objects-in-python-with-zoneinfo/", "published_at": "2026-04-08T06:00:00+00:00" }, { "id": "01a0bba3-aedb-73e8-9010-139a06140eb2", "title": "Creating Python datetime objects with datetime.datetime", "url": "https://lernerpython.com/2026/04/07/creating-python-datetime-objects-with-datetime-datetime/", "published_at": "2026-04-07T06:00:00+00:00" }, { "id": "01a0bba3-aedb-73e8-9010-139a06f3c720", "title": "Python datetime subtraction: Getting a timedelta between two times", "url": "https://lernerpython.com/2026/04/06/python-datetime-subtraction-getting-a-timedelta-between-two-times/", "published_at": "2026-04-06T06:00:00+00:00" }, { "id": "01a0bba3-aedb-73e8-9010-139a07c8a5a7", "title": "Python current date and time: Using datetime.datetime.now()", "url": "https://lernerpython.com/2026/04/05/python-current-date-and-time-using-datetime-datetime-now/", "published_at": "2026-04-05T06:00:00+00:00" }, { "id": "01a0bba3-aedb-73e8-9010-139a08b79327", "title": "pandas date_range: Creating a DatetimeIndex with freq", "url": "https://lernerpython.com/2026/04/04/pandas-date-range-creating-a-datetimeindex-with-freq/", "published_at": "2026-04-04T06:00:00+00:00" }, { "id": "01a0bba9-0006-709a-b185-e79f9895daad", "title": "pd.date_range: Evenly spaced Pandas dates with periods", "url": "https://lernerpython.com/2026/04/03/pd-date-range-evenly-spaced-pandas-dates-with-periods/", "published_at": "2026-04-03T06:00:00+00:00" }, { "id": "01a0bba9-0006-709a-b185-e79f996a757a", "title": "Pandas datetime filtering: Rows before now with pd.Timestamp.now()", "url": "https://lernerpython.com/2026/04/02/pandas-datetime-filtering-rows-before-now-with-pd-timestamp-now/", "published_at": "2026-04-02T06:00:00+00:00" }, { "id": "01a0bba9-0006-709a-b185-e79f997e3e83", "title": "Pandas .str.contains: Finding and filtering rows by substring", "url": "https://lernerpython.com/2026/04/01/pandas-str-contains-finding-and-filtering-rows-by-substring/", "published_at": "2026-04-01T06:00:00+00:00" }, { "id": "01a0bba9-0006-709a-b185-e79f9a215385", "title": "Python keyword-only parameters: Setting default values", "url": "https://lernerpython.com/2026/03/31/python-keyword-only-parameters-setting-default-values/", "published_at": "2026-03-31T06:00:00+00:00" }, { "id": "01a0bba9-0006-709a-b185-e79f9a421912", "title": "Python keyword-only parameters: Using * and *args in def", "url": "https://lernerpython.com/2026/03/30/python-keyword-only-parameters-using-and-args-in-def/", "published_at": "2026-03-30T06:00:00+00:00" }, { "id": "01a0bba9-0007-70f2-a4d0-dfaa5fae83e8", "title": "Type hints for *args in Python: Annotate the element type", "url": "https://lernerpython.com/2026/03/29/type-hints-for-args-in-python-annotate-the-element-type/", "published_at": "2026-03-29T06:00:00+00:00" }, { "id": "01a0bba9-0007-70f2-a4d0-dfaa6076f1a7", "title": "Python *args: Collecting positional arguments into a tuple", "url": "https://lernerpython.com/2026/03/28/python-args-collecting-positional-arguments-into-a-tuple/", "published_at": "2026-03-28T06:00:00+00:00" }, { "id": "01a0bba9-0007-70f2-a4d0-dfaa60a9e912", "title": "Python *args: Accepting any number of positional arguments", "url": "https://lernerpython.com/2026/03/27/python-args-accepting-any-number-of-positional-arguments/", "published_at": "2026-03-27T06:00:00+00:00" }, { "id": "01a0bba9-0007-70f2-a4d0-dfaa60dcafc5", "title": "Positional vs keyword arguments in Python function calls", "url": "https://lernerpython.com/2026/03/26/positional-vs-keyword-arguments-in-python-function-calls/", "published_at": "2026-03-26T07:00:00+00:00" }, { "id": "01a0bba9-0007-70f2-a4d0-dfaa610df433", "title": "Python 3.15 lazy imports: Deferring module load until first use", "url": "https://lernerpython.com/2026/03/25/python-3-15-lazy-imports-deferring-module-load-until-first-use/", "published_at": "2026-03-25T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-1809ffb72f4f", "title": "Python dict keys: Why custom objects work but lists don’t", "url": "https://lernerpython.com/2026/03/24/python-dict-keys-why-custom-objects-work-but-lists-dont/", "published_at": "2026-03-24T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a009c327d", "title": "Python dict keys must be hashable: Why lists don’t work", "url": "https://lernerpython.com/2026/03/23/python-dict-keys-must-be-hashable-why-lists-dont-work/", "published_at": "2026-03-23T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a0130d7c3", "title": "Do you teach Python? Then check out course-setup", "url": "https://lernerpython.com/2026/03/22/do-you-teach-python-then-check-out-course-setup/", "published_at": "2026-03-22T15:10:28+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a02010684", "title": "Pandas str.split: Get the first item of a comma-separated column", "url": "https://lernerpython.com/2026/03/22/pandas-str-split-get-the-first-item-of-a-comma-separated-column/", "published_at": "2026-03-22T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a02025af5", "title": "Pandas str.isdigit: Checking whether strings contain only digits", "url": "https://lernerpython.com/2026/03/21/pandas-str-isdigit-checking-whether-strings-contain-only-digits/", "published_at": "2026-03-21T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a02f0afc3", "title": "Pandas string slicing: Extracting substrings with .str.slice", "url": "https://lernerpython.com/2026/03/20/pandas-string-slicing-extracting-substrings-with-str-slice/", "published_at": "2026-03-20T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a03eaefc7", "title": "Pandas .str.get: Retrieving characters from string columns", "url": "https://lernerpython.com/2026/03/19/pandas-str-get-retrieving-characters-from-string-columns/", "published_at": "2026-03-19T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a049edad4", "title": "Pandas MultiIndex: Dropping a level with reset_index(drop=True)", "url": "https://lernerpython.com/2026/03/18/pandas-multiindex-dropping-a-level-with-reset-index-drop-true/", "published_at": "2026-03-18T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a04f82b4f", "title": "Pandas reset_index: Moving multi-index levels back to columns", "url": "https://lernerpython.com/2026/03/17/pandas-reset-index-moving-multi-index-levels-back-to-columns/", "published_at": "2026-03-17T07:00:00+00:00" }, { "id": "01a0bbae-0209-7290-85ae-180a05315c42", "title": "Pandas reset_index: Turning a data frame’s index into a column", "url": "https://lernerpython.com/2026/03/16/pandas-reset-index-turning-a-data-frames-index-into-a-column/", "published_at": "2026-03-16T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd127b3f16", "title": "Pandas set_index: Turning columns into a data frame index", "url": "https://lernerpython.com/2026/03/15/pandas-set-index-turning-columns-into-a-data-frame-index/", "published_at": "2026-03-15T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd1289da8e", "title": "Multi-line f-strings in Python: Triple quotes with interpolation", "url": "https://lernerpython.com/2026/03/14/multi-line-f-strings-in-python-triple-quotes-with-interpolation/", "published_at": "2026-03-14T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd12c64141", "title": "Python multiline strings: \\n versus triple quotes", "url": "https://lernerpython.com/2026/03/13/python-multiline-strings-n-versus-triple-quotes/", "published_at": "2026-03-13T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd132d36e7", "title": "Python string quotes: Handling an apostrophe inside a string", "url": "https://lernerpython.com/2026/03/12/python-string-quotes-handling-an-apostrophe-inside-a-string/", "published_at": "2026-03-12T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd13d2f2b9", "title": "Reading binary files in Python: Use ‘rb’ mode to get bytes", "url": "https://lernerpython.com/2026/03/11/reading-binary-files-in-python-use-rb-mode-to-get-bytes/", "published_at": "2026-03-11T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd14a8c962", "title": "functools.total_ordering: Define two comparison methods, get six", "url": "https://lernerpython.com/2026/03/10/functools-total-ordering-define-two-comparison-methods-get-six/", "published_at": "2026-03-10T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd1565eb1d", "title": "Python `__all__`: Blocking wildcard imports with a fake name", "url": "https://lernerpython.com/2026/03/09/python-all-blocking-wildcard-imports-with-a-fake-name/", "published_at": "2026-03-09T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd15ecfdf6", "title": "Python __all__: Controlling which names import * exports", "url": "https://lernerpython.com/2026/03/08/python-all-controlling-which-names-import-exports/", "published_at": "2026-03-08T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd1611a8be", "title": "Wildcard imports in Python: Why from module import * is a bad idea", "url": "https://lernerpython.com/2026/03/07/wildcard-imports-in-python-why-from-module-import-is-a-bad-idea/", "published_at": "2026-03-07T07:00:00+00:00" }, { "id": "01a0bbb3-0166-7298-a090-86fd16f21f5a", "title": "Python even/odd checks: Using truthiness instead of == 0", "url": "https://lernerpython.com/2026/03/06/python-even-odd-checks-using-truthiness-instead-of-0/", "published_at": "2026-03-06T07:00:00+00:00" }, { "id": "01a0bbb8-8c9f-73cd-a52b-399dbfba2d90", "title": "Pandas astype errors=’ignore’: Skip failed dtype conversions", "url": "https://lernerpython.com/2026/03/05/pandas-astype-errors-ignore-skip-failed-dtype-conversions/", "published_at": "2026-03-05T07:00:00+00:00" }, { "id": "01a0bbb8-8c9f-73cd-a52b-399dc0b11e71", "title": "Pandas astype() returns a new Series instead of converting in place", "url": "https://lernerpython.com/2026/03/04/pandas-astype-returns-a-new-series-instead-of-converting-in-place/", "published_at": "2026-03-04T07:00:00+00:00" }, { "id": "01a0bbb8-8c9f-73cd-a52b-399dc0eabb19", "title": "Counting NaN values in a Pandas DataFrame with isna and sum", "url": "https://lernerpython.com/2026/03/03/counting-nan-values-in-a-pandas-dataframe-with-isna-and-sum/", "published_at": "2026-03-03T07:00:00+00:00" }, { "id": "01a0bbb8-8c9f-73cd-a52b-399dc16b9f7e", "title": "Counting NaN values in a Pandas series with isna and sum", "url": "https://lernerpython.com/2026/03/02/counting-nan-values-in-a-pandas-series-with-isna-and-sum/", "published_at": "2026-03-02T07:00:00+00:00" } ] posts Claim your blog

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2026

isinstance vs type(): The safer way to check Python types original ↗

6 Jun 2026

Python inheritance: When to use it and when to prefer composition original ↗

5 Jun 2026

Python metaclasses: How they work and when to use a decorator instead original ↗

4 Jun 2026

Python metaclasses: How type.__new__ and type.__init__ create classes original ↗

3 Jun 2026

object and type in Python: The circular class hierarchy original ↗

2 Jun 2026

Python MRO errors: Why child classes must precede parents original ↗

1 Jun 2026

super() without arguments: How Python finds self and the MRO original ↗

31 May 2026

Python cooperative inheritance: How super() walks the MRO original ↗

30 May 2026

Python multiple inheritance: How super() follows the MRO original ↗

29 May 2026

Python multiple inheritance: Why every class needs super()original ↗

28 May 2026

Python multiple inheritance: Which __init__ actually runs original ↗

27 May 2026

Python multiple inheritance: Listing parents with __bases__original ↗

26 May 2026

Python super() and the MRO: How method lookup climbs the hierarchy original ↗

25 May 2026

Python inheritance: Skipping super().__init__ loses parent attributes original ↗

24 May 2026

Python super().__init__: Passing arguments to the parent class original ↗

23 May 2026

Python super(): Misspelled method names raise AttributeError original ↗

22 May 2026

Python’s super(): A proxy for calling parent-class methods original ↗

21 May 2026

Python method overriding: Child methods replace the parent’s original ↗

20 May 2026

Is Python becoming Pinyin?original ↗

19 May 2026

Python method resolution order: Inheriting methods from a parent original ↗

19 May 2026

Python method resolution order: Reading a class’s __mro__original ↗

18 May 2026

Python class inheritance: Subclassing, __bases__, and isinstance original ↗

17 May 2026

Python attributes: Instance variables, class variables, and methods original ↗

16 May 2026

Python attribute lookup: The ICPO rule for finding methods original ↗

15 May 2026

Python `__bases__`: Every class inherits from object original ↗

14 May 2026

Composition in Python classes: The has-a relationship original ↗

13 May 2026

Python composition vs inheritance: The has-a and is-a relationships original ↗

12 May 2026

Python ternary operator: When to use if-elif-else instead original ↗

11 May 2026

Python lambda if-else: Use the ternary operator instead original ↗

10 May 2026

Python’s ternary operator: Conditional expressions in comprehensions original ↗

9 May 2026

Python `__format__`: Define your own format specification syntax original ↗

8 May 2026

Python __format__: Detecting an empty format code original ↗

7 May 2026

Python `__format__`: Custom format codes for your own classes original ↗

6 May 2026

f-string conversion flags: Using !r to get repr instead of str original ↗

5 May 2026

Formatting a Python datetime with f-strings and strftime codes original ↗

4 May 2026

Thousands separators in Python f-strings: Format with commas original ↗

3 May 2026

Python float to percentage: Format with % in an f-string original ↗

2 May 2026

Formatting floats in Python f-strings: The .nf specifier original ↗

1 May 2026

Python f-string format specifiers: Padding and aligning columns original ↗

30 Apr 2026

Python f-string format specifiers: Aligning and padding text original ↗

29 Apr 2026

Python f-string debugging: Printing expressions with =original ↗

28 Apr 2026

Python f-strings are just strings: Use them anywhere original ↗

27 Apr 2026

Python f-strings: Embedding expressions inside strings original ↗

26 Apr 2026

Pandas datetime rounding: dt.floor, dt.ceil, and dt.round original ↗

25 Apr 2026

Pandas dt.normalize: Setting datetime times to midnight original ↗

24 Apr 2026

Pandas datetime to Unix time with astype(‘int64’)original ↗

23 Apr 2026

Convert Unix timestamps to datetime in Pandas with pd.to_datetime original ↗

22 Apr 2026

Pandas to_period: Comparing dates by month, quarter, or year original ↗

21 Apr 2026

Pandas to_period: Finding which period contains a datetime original ↗

20 Apr 2026

Find leap years in a Pandas datetime series with dt.is_leap_year original ↗

19 Apr 2026

Pandas dt.is_month_start: Checking period boundaries in a series original ↗

18 Apr 2026

Getting the day of week with `dt.day_of_week` in Pandas original ↗

17 Apr 2026

Pandas .dt accessor: Extracting year, hour, and day_of_week original ↗

16 Apr 2026

pandas read_csv date parsing: Using the date_format keyword original ↗

15 Apr 2026

Take agentic coding to the next level original ↗

14 Apr 2026

Pandas parse_dates: Reading CSV date columns as datetimes original ↗

14 Apr 2026

pd.to_datetime: Converting a pandas string column to datetimes original ↗

13 Apr 2026

Parse ISO date strings in Python with datetime.fromisoformat original ↗

12 Apr 2026

Python strptime vs. strftime: Parsing versus formatting dates original ↗

11 Apr 2026

Python string to datetime: Parsing dates with strptime original ↗

10 Apr 2026

Python datetime formatting: Using strftime for date strings original ↗

9 Apr 2026

Timezone-aware datetime objects in Python with zoneinfo original ↗

8 Apr 2026

Creating Python datetime objects with datetime.datetime original ↗

7 Apr 2026

Python datetime subtraction: Getting a timedelta between two times original ↗

6 Apr 2026

Python current date and time: Using datetime.datetime.now()original ↗

5 Apr 2026

pandas date_range: Creating a DatetimeIndex with freq original ↗

4 Apr 2026

pd.date_range: Evenly spaced Pandas dates with periods original ↗

3 Apr 2026

Pandas datetime filtering: Rows before now with pd.Timestamp.now()original ↗

2 Apr 2026

Pandas .str.contains: Finding and filtering rows by substring original ↗

1 Apr 2026

Python keyword-only parameters: Setting default values original ↗

31 Mar 2026

Python keyword-only parameters: Using * and *args in def original ↗

30 Mar 2026

Type hints for *args in Python: Annotate the element type original ↗

29 Mar 2026

Python *args: Collecting positional arguments into a tuple original ↗

28 Mar 2026

Python *args: Accepting any number of positional arguments original ↗

27 Mar 2026

Positional vs keyword arguments in Python function calls original ↗

26 Mar 2026

Python 3.15 lazy imports: Deferring module load until first use original ↗

25 Mar 2026

Python dict keys: Why custom objects work but lists don’t original ↗

24 Mar 2026

Python dict keys must be hashable: Why lists don’t work original ↗

23 Mar 2026

Do you teach Python? Then check out course-setup original ↗

22 Mar 2026

Pandas str.split: Get the first item of a comma-separated column original ↗

22 Mar 2026

Pandas str.isdigit: Checking whether strings contain only digits original ↗

21 Mar 2026

Pandas string slicing: Extracting substrings with .str.slice original ↗

20 Mar 2026

Pandas .str.get: Retrieving characters from string columns original ↗

19 Mar 2026

Pandas MultiIndex: Dropping a level with reset_index(drop=True)original ↗

18 Mar 2026

Pandas reset_index: Moving multi-index levels back to columns original ↗

17 Mar 2026

Pandas reset_index: Turning a data frame’s index into a column original ↗

16 Mar 2026

Pandas set_index: Turning columns into a data frame index original ↗

15 Mar 2026

Multi-line f-strings in Python: Triple quotes with interpolation original ↗

14 Mar 2026

Python multiline strings: \n versus triple quotes original ↗

13 Mar 2026

Python string quotes: Handling an apostrophe inside a string original ↗

12 Mar 2026

Reading binary files in Python: Use ‘rb’ mode to get bytes original ↗

11 Mar 2026

functools.total_ordering: Define two comparison methods, get six original ↗

10 Mar 2026

Python `__all__`: Blocking wildcard imports with a fake name original ↗

9 Mar 2026

Python __all__: Controlling which names import * exports original ↗

8 Mar 2026

Wildcard imports in Python: Why from module import * is a bad idea original ↗

7 Mar 2026

Python even/odd checks: Using truthiness instead of == 0 original ↗

6 Mar 2026

Pandas astype errors=’ignore’: Skip failed dtype conversions original ↗

5 Mar 2026

Pandas astype() returns a new Series instead of converting in place original ↗

4 Mar 2026

Counting NaN values in a Pandas DataFrame with isna and sum original ↗

3 Mar 2026

Counting NaN values in a Pandas series with isna and sum original ↗

2 Mar 2026