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Installing python module within code

...upported by pip. Furthermore since pip v10, all code has been moved to pip._internal precisely in order to make it clear to users that programmatic use of pip is not allowed. Use sys.executable to ensure that you will call the same pip associated with the current runtime. import subprocess import ...
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Why do we always prefer using parameters in SQL statements?

... the SQL statement is not going to be the same – marc_s Sep 21 '11 at 20:57 1 that means sql inje...
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How is a CRC32 checksum calculated?

... 1100001010 = Quotient (nobody cares about the quotient) _______________ 10011 ) 11010110110000 = Augmented message (1101011011 + 0000) =Poly 10011,,.,,.... -----,,.,,.... 10011,.,,.... 10011,.,,.... -----,.,,.... 00001.,,.... ...
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'id' is a bad variable name in Python

...() is a fundamental built-in: Help on built-in function id in module __builtin__: id(...) id(object) -> integer Return the identity of an object. This is guaranteed to be unique among simultaneously existing objects. (Hint: it's the object's memory address.) In g...
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?

...oes. Here's 2.7: >>> dis.dis('True == 1') 1 0 LOAD_GLOBAL 0 (True) 3 LOAD_CONST 1 (1) 6 COMPARE_OP 2 (==) 9 RETURN_VALUE >>> dis.dis('True == 1') 1 0 LOAD_GLOBAL ...
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What is the maximum recursion depth in Python, and how to increase it?

...mple context manager like this: import sys class recursionlimit: def __init__(self, limit): self.limit = limit self.old_limit = sys.getrecursionlimit() def __enter__(self): sys.setrecursionlimit(self.limit) def __exit__(self, type, value, tb): sys.setr...
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Pandas - How to flatten a hierarchical index in columns

... would be to set the columns to the top level: df.columns = df.columns.get_level_values(0) Note: if the to level has a name you can also access it by this, rather than 0. . If you want to combine/join your MultiIndex into one Index (assuming you have just string entries in your columns) you cou...
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How can I check for Python version in a program that uses new language features?

...oesn't have ternary Also, with is available in Python 2.5, just add from __future__ import with_statement. EDIT: to get control early enough, you could split it into different .py files and check compatibility in the main file before importing (e.g. in __init__.py in a package): # __init__.py #...
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Determine if variable is defined in Python [duplicate]

...() if you want to be pedantic, you can check the builtins too 'a' in vars(__builtins__) share | improve this answer | follow | ...
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Any reason not to use '+' to concatenate two strings?

...ucture, especially if it is growing. With list you can use list.extend(list_of_items) and list.append(item) which are much faster when concatenating stuff dynamically. – Antti Haapala Sep 11 '12 at 9:56 ...