imp -- Python library reference
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3.8. Built-in Module imp
This module provides an interface to the mechanisms used to implement
the import
statement. It defines the following constants and
functions:
- get_magic () -- function of module imp
-
Return the magic string value used to recognize byte-compiled code
files (``
.pyc
files'').
- get_suffixes () -- function of module imp
-
Return a list of triples, each describing a particular type of file.
Each triple has the form
(suffix, mode,
type)
, where suffix is a string to be appended to the
module name to form the filename to search for, mode is the mode
string to pass to the built-in open
function to open the file
(this can be 'r'
for text files or 'rb'
for binary
files), and type is the file type, which has one of the values
PY_SOURCE
, PY_COMPILED
or C_EXTENSION
, defined
below. (System-dependent values may also be returned.)
- find_module (name, [path]) -- function of module imp
-
Try to find the module name on the search path path. The
default path is
sys.path
. The return value is a triple
(file, pathname, description)
where
file is an open file object positioned at the beginning,
pathname is the pathname of the
file found, and description is a triple as contained in the list
returned by get_suffixes
describing the kind of file found.
- init_builtin (name) -- function of module imp
-
Initialize the built-in module called name and return its module
object. If the module was already initialized, it will be initialized
again. A few modules cannot be initialized twice --- attempting
to initialize these again will raise an
ImportError
exception.
If there is no
built-in module called name, None
is returned.
- init_frozen (name) -- function of module imp
-
Initialize the frozen module called name and return its module
object. If the module was already initialized, it will be initialized
again. If there is no frozen module called name,
None
is returned. (Frozen modules are modules written in
Python whose compiled byte-code object is incorporated into a
custom-built Python interpreter by Python's freeze
utility.
See Tools/freeze
for now.)
- is_builtin (name) -- function of module imp
-
Return
1
if there is a built-in module called name which can be
initialized again. Return -1
if there is a built-in module
called name which cannot be initialized again (see
init_builtin
). Return 0
if there is no built-in module
called name.
- is_frozen (name) -- function of module imp
-
Return
1
if there is a frozen module (see init_frozen
)
called name, 0
if there is no such module.
- load_compiled (name, pathname, [file]) -- function of module imp
-
Load and initialize a module implemented as a byte-compiled code file
and return its module object. If the module was already initialized,
it will be initialized again. The name argument is used
to create or access a module object. The pathname argument
points to the byte-compiled code file. The optional file
argument is the byte-compiled code file, open for reading in binary
mode, from the beginning --- if not given, the function opens
pathname. It must currently be a real file object, not a
user-defined class emulating a file.
- load_dynamic (name, pathname, [file]) -- function of module imp
-
Load and initialize a module implemented as a dynamically loadable
shared library and return its module object. If the module was
already initialized, it will be initialized again. Some modules
don't like that and may raise an exception. The pathname
argument must point to the shared library. The name argument is
used to construct the name of the initialization function: an external
C function called
initname()
in the shared library is
called. The optional file argment is ignored. (Note: using
shared libraries is highly system dependent, and not all systems
support it.)
- load_source (name, pathname, [file]) -- function of module imp
-
Load and initialize a module implemented as a Python source file and
return its module object. If the module was already initialized, it
will be initialized again. The name argument is used to
create or access a module object. The pathname argument points
to the source file. The optional file argument is the source
file, open for reading as text, from the beginning --- if not given,
the function opens pathname. It must currently be a real file
object, not a user-defined class emulating a file. Note that if a
properly matching byte-compiled file (with suffix
.pyc
) exists,
it will be used instead of parsing the given source file.
- new_module (name) -- function of module imp
-
Return a new empty module object called name. This object is
not inserted in
sys.modules
.
The following constants with integer values, defined in the module,
are used to indicate the search result of imp.find_module
.
- SEARCH_ERROR -- data of module imp
-
The module was not found.
- PY_SOURCE -- data of module imp
-
The module was found as a source file.
- PY_COMPILED -- data of module imp
-
The module was found as a compiled code object file.
- C_EXTENSION -- data of module imp
-
The module was found as dynamically loadable shared library.
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