python获取帮助_python获取帮助

１．help()

>>> help()

Welcome to Python 3.5's help utility!

If this is your first time using Python, you should definitely check out

the tutorial on the Internet at http://docs.python.org/3.5/tutorial/.

Enter the name of any module, keyword, or topic to get help on writing

Python programs and using Python modules. To quit this help utility and

return to the interpreter, just type "quit".

To get a list of available modules, keywords, symbols, or topics, type

"modules", "keywords", "symbols", or "topics". Each module also comes

with a one-line summary of what it does; to list the modules whose name

or summary contain a given string such as "spam", type "modules spam".

help>

help> int

Help on class int in module builtins:

class int(object)

| int(x=0) -> integer

| int(x, base=10) -> integer

|

| Convert a number or string to an integer, or return 0 if no arguments

| are given. If x is a number, return x.__int__(). For floating point

| numbers, this truncates towards zero.

|

| If x is not a number or if base is given, then x must be a string,

| bytes, or bytearray instance representing an integer literal in the

| given base. The literal can be preceded by '+' or '-' and be surrounded

| by whitespace. The base defaults to 10. Valid bases are 0 and 2-36.

| Base 0 means to interpret the base from the string as an integer literal.

| >>> int('0b100', base=0)

| 4

|

| Methods defined here:

|

| __abs__(self, /)

| abs(self)

help> string

Help on module string:

NAME

string - A collection of string constants.

MODULE REFERENCE

https://docs.python.org/3.5/library/string.html

The following documentation is automatically generated from the Python

source files. It may be incomplete, incorrect or include features that

are considered implementation detail and may vary between Python

implementations. When in doubt, consult the module reference at the

location listed above.

DESCRIPTION

Public module variables:

whitespace -- a string containing all ASCII whitespace

ascii_lowercase -- a string containing all ASCII lowercase letters

ascii_uppercase -- a string containing all ASCII uppercase letters

>>> help(abs)

Help on built-in function abs in module builtins:

abs(x, /)

Return the absolute value of the argument.

Help on built-in module math:

>>> help(math)

Help on built-in module math:

NAME

math

DESCRIPTION

This module is always available. It provides access to the

mathematical functions defined by the C standard.

FUNCTIONS

acos(...)

acos(x)

Return the arc cosine (measured in radians) of x.2.  dir()

dir(...)

dir([object]) -> list of strings

If called without an argument, return the names in the current scope.

Else, return an alphabetized list of names comprising (some of) the attributes

of the given object, and of attributes reachable from it.

3. __doc__

>>> math.__doc__

'This module is always available. It provides access to the\nmathematical functions defined by the C standard.'

>>> abs.__doc__

'Return the absolute value of the argument.'

>>> S="123"

>>> print(S.upper().__doc__)

str(object='') -> str

str(bytes_or_buffer[, encoding[, errors]]) -> str

Create a new string object from the given object. If encoding or

errors is specified, then the object must expose a data buffer

that will be decoded using the given encoding and error handler.

Otherwise, returns the result of object.__str__() (if defined)

or repr(object).

encoding defaults to sys.getdefaultencoding().

errors defaults to 'strict'.