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Automatic creation date for Django model form objects?
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319
You can use the auto_now and auto_now_add options for updated_at and created_at respectively.
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SQLite table constraint - unique on multiple columns
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348
Put the UNIQUE declaration within the column definition section; working example:
CREATE TABL...
Pandas: drop a level from a multi-level column index?
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321
You can use MultiIndex.droplevel:
>>> cols = pd.MultiIndex.from_tuples([("a", "b"), ...
Difference between FOR and AFTER triggers?
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3 Answers
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How can I combine flexbox and vertical scroll in a full-height app?
...flexbox layout module ( display: box; and other things) in this link: CSS3 Flexbox full-height app and overflow
3 Answers...
Django - filtering on foreign key properties
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Way to read first few lines for pandas dataframe
...ms to work. Using one of the standard large test files (988504479 bytes, 5344499 lines):
In [1]: import pandas as pd
In [2]: time z = pd.read_csv("P00000001-ALL.csv", nrows=20)
CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
Wall time: 0.00 s
In [3]: len(z)
Out[3]: 20
In [4]: time z = pd.rea...
How do I draw a grid onto a plot in Python?
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223
You want to use pyplot.grid:
x = numpy.arange(0, 1, 0.05)
y = numpy.power(x, 2)
fig = plt.figu...