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Regular expression to allow spaces between words

... tl;dr Just add a space in your character class. ^[a-zA-Z0-9_ ]*$   Now, if you want to be strict... The above isn't exactly correct. Due to the fact that * means zero or more, it would match all of the following cases that one would not usually mean to match: An empty string...
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Get Image size WITHOUT loading image into memory

... data (or call the load method). Digging deeper, we see that .open calls _open which is a image-format specific overload. Each of the implementations to _open can be found in a new file, eg. .jpeg files are in JpegImagePlugin.py. Let's look at that one in depth. Here things seem to get a bit tric...
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Extending the User model with custom fields in Django

...o.contrib.auth.models import User from django.db.models.signals import post_save class UserProfile(models.Model): user = models.OneToOneField(User) #other fields here def __str__(self): return "%s's profile" % self.user def create_user_profile(sender, instance, creat...
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Python: What OS am I running on?

...ion of Darwin that comes with Catalina 10.15.2: en.wikipedia.org/wiki/MacOS_Catalina#Release_history – philshem Aug 21 at 13:28 add a comment  |  ...
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XmlSerializer: remove unnecessary xsi and xsd namespaces

...uring serialization. public MyTypeWithNamespaces( ) { this._namespaces = new XmlSerializerNamespaces(new XmlQualifiedName[] { // Don't do this!! Microsoft's documentation explicitly says it's not supported. // It doesn't throw any exceptions, but in my testing...
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detach all packages while working in R

...h()[pos]’. This can be an unquoted name or a character string but _not_ a character vector. If a number is supplied this is taken as ‘pos’. So we need to repeatedly call detach() once per element of pkg. There are a couple of other arguments we need to specify to get thi...
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What happens to global and static variables in a shared library when it is dynamically linked?

...yntax similar to the function export/import syntax, i.e.: #ifdef COMPILING_THE_DLL #define MY_DLL_EXPORT extern "C" __declspec(dllexport) #else #define MY_DLL_EXPORT extern "C" __declspec(dllimport) #endif MY_DLL_EXPORT int my_global; When you do that, the global variable is added to the list of...
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how to check if a file is a directory or regular file in python? [duplicate]

... pathname = os.path.join(top, f) mode = os.stat(pathname)[ST_MODE] if S_ISDIR(mode): # It's a directory, recurse into it walktree(pathname, callback) elif S_ISREG(mode): # It's a file, call the callback function callback(...
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Is there a math nCr function in python? [duplicate]

... def nCr(n,r): f = math.factorial return f(n) / f(r) / f(n-r) if __name__ == '__main__': print nCr(4,2) In Python 3, use the integer division // instead of / to avoid overflows: return f(n) // f(r) // f(n-r) Output 6 ...
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Very Long If Statement in Python [duplicate]

...to your code block. For example: if (abcdefghijklmnopqrstuvwxyz > some_other_long_identifier and here_is_another_long_identifier != and_finally_another_long_name): # ... your code here ... pass share ...