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Should all Python classes extend object?
...inheritance are different in ways that I won't even try to summarize here. All good documentation that I've seen about MI describes new-style classes.
Finally, old-style classes have disappeared in Python 3, and inheritance from object has become implicit. So, always prefer new style classes unless...
Convert a String representation of a Dictionary to a dictionary?
...
Starting in Python 2.6 you can use the built-in ast.literal_eval:
>>> import ast
>>> ast.literal_eval("{'muffin' : 'lolz', 'foo' : 'kitty'}")
{'muffin': 'lolz', 'foo': 'kitty'}
This is safer than using eval. As its own docs say:
>>> help(ast.literal_e...
Getting “unixtime” in Java
... platforms (and the year 2038 problem). 64-bit platforms use a larger time_t data type. Java dodged that bullet by using a long as the return for System.currentTimeMillis(). If you convert to int, you're re-introducing the year 2038 problem. See en.wikipedia.org/wiki/Year_2038_problem#Solutions
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java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...
What is the difference between join and merge in Pandas?
...
pandas.merge() is the underlying function used for all merge/join behavior.
DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...
sqlalchemy IS NOT NULL select
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column_obj != None will produce a IS NOT NULL constraint:
In a column context, produces the clause a != b. If the target is None, produces a IS NOT NULL.
or use isnot() (new in 0.7.9):
Implement the IS NOT operator.
...
How to define @Value as optional
...swered Jan 8 '18 at 13:23
alonso_50alonso_50
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Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...
Is it ok to use dashes in Python files when trying to import them?
Basically when I have a python file like:
7 Answers
7
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Duplicate headers received from server
...invalidChars);
string replace = Regex.Replace(name, invalidReStr, "_").Replace(";", "").Replace(",", "");
return replace;
}
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