After three great days at the PyCon US 2017 in Portland, OR Hendrik and I decided to participate in the development sprints succeeding the conferece. The code sprints are an essential part of PyCon, and a chance to meet some of the maintainers and contributors of various open source projects. For us it was the first time attending a code sprint. The day before the sprint there was a session helping people to set up Git, Python (including virtual environments) and getting familiar with version control.

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There are a lot of cases when we want to track time when an entity was created or updated. Here is a simple recipe to make some or all of your SQLAlchemy entities auto-timestamping. To achieve this, we will provide a mixin class. from datetime import datetime from sqlalchemy import Column, DateTime, event class TimeStampMixin(object): """ Timestamping mixin """ created_at = Column(DateTime, default=datetime.utcnow) created_at._creation_order = 9998 updated_at = Column(DateTime, default=datetime.utcnow) updated_at.

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Everyday at work around noon the question of where to get lunch comes up. Normally, we choose between different restataurants in the vicinity of the office. One exception is the HU Mensa (university cafeteria). Despite being really cheap the food quality there varies a lot and it really depends on the daily menu whether a visit is worthwhile. To tackle this issue I decided to spent another IT Open Space putting together a little script that will help us in the future.

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At Project-A we are using Codebase as a project management tool together with its version control. Just as with any other tools you can create tickets and organize them in sprints. Our usual (very simplified) workflow includes: Sprint planning for tickets Priotizing tickets Developer working on tickets Product managers verifying if the tickets were implemented as intended Unfortunately, sometimes your backlog keeps growing and tickets are no longer valid, outdated or, in the worst case, just forgotten.

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After collecting some photovoltaic data using PikoPy and a some readings from the residential meter it was time to put everything together. The data is collected by a couple of scripts triggered by a cronjob every five minutes. $ crontab -l */5 * * * * python /home/solarpi/kostal_piko.py */5 * * * * python /home/solarpi/collect_meter.py */15 * * * * python /home/solarpi/collect_weather.py The results are then written into a SQLite database.

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The first step of my plan, building a Raspberry Pi based photovoltaic monitoring solution, is finished. I created a python package that works with the Kostal Piko 5.5 inverter (and theoretically should work with other Kostal inverters as well) and offers a clean interface for accessing the data: import pikopy #create a new piko instance p = Piko('host', 'username', 'password') #get current power print p.get_current_power() #get voltage from string 1 print p.

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After the 2013 Berlin Marathon sold out in less than four hours, the organizers decided to alter the registration process for 2014. First there was a pre-registration phase followed by a random selection from the pool of registrants to receive a spot. Those who were selected had to register until November 11th, 2013. Any spots that were not confirmed till the 11th would be offered to pre-registered candidates according to the order in which they were randomly selected.

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A couple of years ago I was on a trip to Budapest with a couple of friends. While roaming the streets we were passing by a casino and my friend insisted that there was a perfect strategy that would only lead to winning at roulette tables. Curious as I was I had him explain his theory. The system basically works as follows: First, you place a coin on red. If red wins, take your winning and start over.

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Christian Stade-Schuldt

Data Engineer @ HERE IoT innovation lab| Full-time geek | Cyclist | Learning from data

Data Engineer @ HERE

Berlin, Germany