Python Modules List Error
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This module never needs to be imported explicitly: the exceptions are provided in the built-in namespace as well as the exceptions module. For python exceptions list class exceptions, in a try statement with an except clause python filenotfounderror that mentions a particular class, that clause also handles any exception classes derived from that class (but not python custom exception exception classes from which it is derived). Two exception classes that are not related via subclassing are never equivalent, even if they have the same name. The built-in exceptions python exception message listed below can be generated by the interpreter or built-in functions. Except where mentioned, they have an "associated value" indicating the detailed cause of the error. This may be a string or a tuple containing several items of information (e.g., an error code and a string explaining the code). The associated value is the second argument to the
Python Valueerror Example
raise statement. If the exception class is derived from the standard root class BaseException, the associated value is present as the exception instance's args attribute. User code can raise built-in exceptions. This can be used to test an exception handler or to report an error condition "just like" the situation in which the interpreter raises the same exception; but beware that there is nothing to prevent user code from raising an inappropriate error. The built-in exception classes can be subclassed to define new exceptions; programmers are encouraged to derive new exceptions from the Exception class or one of its subclasses, and not from BaseException. More information on defining exceptions is available in the Python Tutorial under User-defined Exceptions. The following exceptions are only used as base classes for other exceptions. exception BaseException¶ The base class for all built-in exceptions. It is not meant to be directly inherited by user-defined classes (for that, use Exception). If str() or unicode() is called on an instance of this cl
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Python 3 Exceptions
Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation python exception class methods Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just assertionerror python like you, helping each other. Join them; it only takes a minute: Sign up Python module error up vote 0 down vote favorite Hi I am new to Python I want to use an already developed tool/code and https://docs.python.org/2/library/exceptions.html I have a problem with the modules used. I installed Spider with Anaconda version of Python I am trying to run below code, https://code.google.com/p/quantandfinancial/source/browse/trunk/example_black_litterman.py if I understood the code correctly it is referencing the below custom module https://code.google.com/p/quantandfinancial/source/browse/trunk/structures/quote.py?r=25 I stored the two parts of the code in C:\Users\Michal\Documents\Python Scripts and Python is installed in C:\Anaconda3, when I run the code I get an error File "C:/Users/Michal/Documents/Python Scripts/Black-Litterman.py", line 4, in
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About http://stackoverflow.com/questions/14295680/cannot-import-a-python-module-that-is-definitely-installed-mechanize Us Learn more about Stack Overflow the company Business Learn more about hiring http://python-notes.curiousefficiency.org/en/latest/python_concepts/import_traps.html developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Cannot import a python module that python exception is definitely installed (mechanize) up vote 21 down vote favorite 5 On-going woes with the python (2.7.3) installation on my Ubuntu 12.04 machine and importing modules. Here I am having an issue where I have definitely installed mechanize both on my machine and in various virtual environments. I have tried installing from pip, easy_install and via python setup.py install from this repo: https://github.com/abielr/mechanize. To no avail, python modules list each time, I enter my python interactive and I get: Python 2.7.3 (default, Aug 1 2012, 05:14:39) [GCC 4.6.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import mechanize Traceback (most recent call last): File "
The stale bytecode file trap The submodules are added to the package namespace trap More exotic traps Else Clauses on Loop Statements Various Ideas for Python and CPython Using the Python Kerberos Module General Linux Notes Python Conferences Nick Coghlan's Python Notes Docs » Python Concepts » Traps for the Unwary in Python's Import System Edit on Bitbucket Traps for the Unwary in Python's Import System¶ Python's import system is powerful, but also quite complicated. Until the release of Python 3.3, there was no comprehensive explanation of the expected import semantics, and even following the release of 3.3, the details of how sys.path is initialised are still somewhat challenging to figure out. Even though 3.3 cleaned up a lot of things, it still has to deal with various backwards compatibility issues that can cause strange behaviour, and may need to be understood in order to figure out how some third party frameworks operate. Furthermore, even without invoking any of the more exotic features of the import system, there are quite a few common missteps that come up regularly on mailing lists and Q&A sites like Stack Overflow. This essay only officially covers Python versions back to Python 2.6. Much of it applies to earlier versions as well, but I won't be qualifying any of the explanations with version details before 2.6. As with all my essays on this site, suggestions for improvement or requests for clarification can be posted on BitBucket. The missing __init__.py trap¶ This particular trap applies to 2.x releases, as well as 3.x releases up to and including 3.2. Prior to Python 3.3, filesystem directories, and directories within zipfiles, had to contain an __init__.py in order to be recognised as Python package directories. Even if there is no initialisation code to run when the package is imported, an empty __init__.py file