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You cannot, in general encapsulate Python modules in a single file. Because doing so would destroy the module searching method that python uses (files and directories). If you are not able to install modules on a machine(due to not having enough permissions), you could use either virtualenv or save the module files in another directory and use the following code to allow Python to search for modules in the given module:>>> import os, sys >>> file_path = 'AdditionalModules/' >>> sys.path.append(os.path.dirname(file_path)) >>> # Now python also searches AdditionalModules folder for importing modules as we have set it on the PYTHONPATH.You can ... Read More
For a pure python module you can find the location of the source files by looking at the module.__file__. For example, >>> import mymodule >>> mymodule.__file__ C:/Users/Ayush/mymodule.py Many built in modules, however, are written in C, and therefore module.__file__ points to a .so file (there is no module.__file__ on Windows), and therefore, you can't see the source. You can manually go and check the PYTHONPATH variable contents to find the directories from where these built in modules are being imported. Running "python -v"from the command line tells you what is being imported and from where. This is useful if you want to ... Read More
An identifier in a Python program is name given to various elements in it, such as keyword, variable, function, class, module, package etc. An identifier should start with either an alphabet (lower or upper case) or underscore (_). More than one alpha-numeric characters or underscore may follow.Keywords are predefined. They are in lowercase. They can not be used for any other purpose.By convention, name of class starts with uppercase alphabet. Whereas others start with lowercase alphabet.Single underscore in the beginning of a variable name is used to indicate a private variable.Two underscores in beginning indicate that the variable is strongly ... Read More
Many a times it is required to treat more than one statements in a program as a block. Different programming languages use different techniques to define scope and extent of block of statements in constructs like class, function, conditional and loop. In C and C++ for example, statements inside curly brackets are treated as a block. Python uses uniform indentation to mark block of statements.Before beginning of block symbol : is used. First and subsequent statements in block are written by leaving additional (but uniform) whitespace (called indent) . In order to signal end of block, the whitespace is dedented. ... Read More
json is simplejson, added to the stdlib. But since json was added in 2.6, simplejson has the advantage of working on more Python versions (2.4+).simplejson is also updated more frequently than Python. Although they are the same, the version included in the stdlib doesn't include the latest optimizations. So if you need (or want) the latest version, it's best to use simplejson itself, if possible.A good practice, is to use one or the other as a fallback. For example,try: import simplejson as json except ImportError: import json
locals() returns you a dictionary of variables declared in the local scope while globals() returns you a dictionary of variables declared in the global scope. At global scope, both locals() and globals() return the same dictionary to global namespace. To notice the difference between the two functions, you can call them from within a function. For example, def fun(): var = 123 print "Locals: ", locals() print "Vars: ", vars() print "Globals: ", globals() fun()This will give the output:Locals: {'var': 123} Globals: {'__builtins__': , '__name__': '__main__', 'fun': , '__doc__': None, '__package__': None}vars() ... Read More
The function reload(moduleName) reloads a previously loaded module (assuming you loaded it with the syntax "import moduleName". It is intended for conversational use, where you have edited the source file for a module and want to test it without leaving Python and starting it again. For example, >>> import mymodule >>> # Edited mymodule and want to reload it in this script >>> reload(mymodule)Note that the moduleName is the actual name of the module, not a string containing its name. In Python 3, reload was moved from builtins to imp. So to use reload in Python 3, you'd have to ... Read More
There are multiple ways to get a list of locally installed Python modules. Easiest way is using the Python shell, for example, >>> help('modules') Please wait a moment while I gather a list of all available modules... BaseHTTPServer brain_nose markupbase stat Bastion brain_numpy marshal statvfs CGIHTTPServer brain_pkg_resources math string Canvas brain_pytest matplotlib ... Read More
When you install Python, you also get the Python package manager, pip. You can use pip to get the versions of python modules. If you want to list all installed Python modules with their version numbers, use the following command:$ pip freezeYou will get the output:asn1crypto==0.22.0 astroid==1.5.2 attrs==16.3.0 Automat==0.5.0 backports.functools-lru-cache==1.3 cffi==1.10.0 ...To individually find the version number you can grep on this output on *NIX machines. For example:$ pip freeze | grep PyMySQL PyMySQL==0.7.11On windows, you can use findstr instead of grep. For example:PS C:\> pip freeze | findstr PyMySql PyMySQL==0.7.11If you want to know the version of a module ... Read More
For a pure python module you can find the location of the source files by looking at the module.__file__. For example, >>> import mymodule >>> mymodule.__file__ C:/Users/Ayush/mymodule.py Many built-in modules, however,are written in C, and therefore module.__file__ points to a .so file (there is no module.__file__ on Windows), and therefore, you can't see the source. Running "python -v"from the command line tells you what is being imported and from where. This is useful if you want to know the location of built-in modules.