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Why doesn't print work in a lambda?
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A lambda's body has to be a single expression. In Python 2.x, print is a statement. However, in Python 3, print is a function (and a function application is an expression, so it will work in a lambda). You can (and should, for forward compatibility :) use the back-ported pri...
Explain the “setUp” and “tearDown” Python methods used in test cases
Can anyone explain the use of Python's setUp and tearDown methods while writing test cases apart from that setUp is called immediately before calling the test method and tearDown is called immediately after it has been called?
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Removing a list of characters in string
I want to remove characters in a string in python:
18 Answers
18
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Python Regex - How to Get Positions and Values of Matches
...m.group()
'message'
>>> m.span()
(4, 11)
Combine that with:
In Python 2.2, the finditer() method is also available, returning a sequence of MatchObject instances as an iterator.
>>> p = re.compile( ... )
>>> iterator = p.finditer('12 drummers drumming, 11 ... 10 ...')
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How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
In Python, the only way I can find to concatenate two lists is list.extend , which modifies the first list. Is there any concatenation function that returns its result without modifying its arguments?
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Why do some functions have underscores “__” before and after the function name?
...seems to occur a lot, and I was wondering if this was a requirement in the Python language, or merely a matter of convention?
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How do I get the opposite (negation) of a Boolean in Python?
...ll __bool__ on the object.
So by implementing __bool__ (or __nonzero__ in Python 2) you can customize the truth value and thus the result of not:
class Test(object):
def __init__(self, value):
self._value = value
def __bool__(self):
print('__bool__ called on {!r}'.format(s...
Haversine Formula in Python (Bearing and Distance between two GPS points)
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Here's a Python version:
from math import radians, cos, sin, asin, sqrt
def haversine(lon1, lat1, lon2, lat2):
"""
Calculate the great circle distance between two points
on the earth (specified in decimal degrees)
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How to capture stdout output from a Python function call?
I'm using a Python library that does something to an object
3 Answers
3
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Loop through all nested dictionary values?
...error:
RuntimeError: maximum recursion depth exceeded while calling a Python object
The same goes with the implementation from senderle.
Similarly, you get an infinite loop with this implementation from Fred Foo:
def myprint(d):
stack = list(d.items())
while stack:
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