python-utils-rondomondo 0.1.4

Reusable Python utilities for dates, money, and more

python-utils-rondomondo

Reusable Python utilities for dates and money.

Install

pip install python-utils-rondomondo

Or with uv:

uv add python-utils-rondomondo

Usage

from python_utils.dates import now_utc, parse_duration, date_windows
from python_utils.money import to_money, fmt_accounting, format_currency, allocate

Dates

Function	Description
now_utc(microsecond=False)	Current UTC datetime, always timezone-aware
to_iso(dt, timespec="seconds")	Format datetime as ISO 8601 string (space separator)
from_iso(s)	Parse ISO 8601 string to datetime
parse_duration(s)	Parse human duration like "7days", "3hrs", "90secs" to timedelta
midnight_before(dt)	Midnight at the start of the day before dt
date_windows(start, end, window)	Split a range into non-overlapping timedelta windows
is_leap(year)	True if the given year is a leap year
same_day_next_year(dt)	Advance by one calendar year, clamping Feb 29 to Feb 28

from python_utils.dates import now_utc, parse_duration, date_windows, to_iso
from datetime import timedelta

now = now_utc()
end = now + parse_duration("7days")
windows = date_windows(now, end, timedelta(days=2))
print(to_iso(now))  # '2026-05-19 14:30:00+00:00'

Money

Function	Description
to_money(value)	Convert str, int, or Decimal to a cent-quantised Decimal (half-up)
to_decimal(value)	Convert int, float, str, or Decimal to Decimal without rounding
round_half_up(amount, places=2)	Round using half-up convention
round_bankers(amount, places=2)	Round using banker's rounding (half to even)
truncate(amount, places=2)	Truncate toward zero
format_currency(amount, symbol="$", thousands=True)	Format Decimal as a currency string
parse_currency(s)	Parse a currency string like "$1,234.56" or "-£99.00" to Decimal
fmt_accounting(value)	Accounting convention: negatives as (120.00), positives as 500.00
allocate(amount, ratios)	Distribute amount across ratios with no penny lost or gained

from decimal import Decimal
from python_utils.money import to_money, format_currency, fmt_accounting, allocate

price = to_money("19.99")
tax   = to_money(price * Decimal("0.1"))  # 2.00
total = price + tax                       # 21.99

print(format_currency(total))             # '$21.99'
print(fmt_accounting(Decimal("-120.00"))) # '(120.00)'
print(fmt_accounting(Decimal("500.00"))) # '500.00 '

shares = allocate(Decimal("100.00"), [1, 2, 3])  # [33.33, 33.33, 33.34] (sums exactly)

Examples

F-string formatting reference

src/python_utils/examples/fstrings.py is a runnable reference script covering the full range of Python f-string format specs, using an invoice as the running example:

• Number formatting: decimal places, thousands separators, alignment, currency symbols
• Sign formatting: explicit +, space padding, accounting parentheses
• Integer bases: hex, octal, binary, scientific notation, percent
• String alignment, padding, fill characters, truncation
• Expressions, conditionals, and method calls inside f-strings
• Conversion flags: !s, !r, !a
• A complete invoice table tying all patterns together

python src/python_utils/examples/fstrings.py

Requirements

Python 3.12+

License

MIT