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Mac Python.
, Python Windows, Python cmd.exe
:
C:\Users\Your Name>python --version
, python Linux Mac, Linux Mac :
python --version
, python, -: https://www.python.org/
Python - , , Python .py
, Python .
Python :
C:\Users\Your Name>python helloworld.py
helloworld.py
- python.
Python helloworld.py
, .
print("Hello, World!")
. , , , :
C:\Users\Your Name>python helloworld.py
:
Hello, World!
, Python.
Python
Python, . , Python .
Windows, Mac Linux :
C:\Users\Your Name>python
, python
, py
:
C:\Users\Your Name>py
Python, hello world :
C:\Users\Your Name>python Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:04:45) [MSC v.1900 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or "license" for more information. >>> print("Hello, World!")
"Hello, World!" :
C:\Users\Your Name>python Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:04:45) [MSC v.1900 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or "license" for more information. >>> print("Hello, World!") Hello, World!
Python, , Python:
exit()
1.
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Python . , 1
one
(). :
one = 1
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one
.
two = 2 some_number = 10000
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2
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# booleans ( ) true_boolean = True false_boolean = False # string () my_name = "Leandro Tk" # float ( ) book_price = 15.80
#
, Python :
2. :
if
, . True
, , if
. :
if True: print("Hello Python If") if 2 > 1: print("2 is greater than 1")
, if
. , Python . Python . , .
2
1
, print
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print ()
.
if 1 > 2: print("1 is greater than 2") else: print("1 is not greater than 2")
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1
2
, else
.
elif
, else if:
if 1 > 2: print("1 is greater than 2") elif 2 > 1: print("1 is not greater than 2") else: print("1 is equal to 2")
3. /
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for
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while
: True
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10
.
num = 1 while num <= 10: print(num) num += 1
while
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11
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.
, :
loop_condition = True while loop_condition: print("Loop Condition keeps: %s" %(loop_condition)) loop_condition = False
loop_condition
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for
: num
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10
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for i in range(1, 11): print(i)
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List
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my_integers = [1, 2, 3, 4, 5]
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Array: [5][7][1][3][4] Index: [0][1][2][3][4]
Python, :
my_integers = [5, 7, 1, 3, 4] print(my_integers[0]) # 5 print(my_integers[1]) # 7 print(my_integers[4]) # 4
, . , , . :
relatives_names = [ "Alex", "Juliana", "Max", "Bruno", "Kaio" ] print(relatives_names[4]) # Kaio
, . .
, List
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List
- append
. , :
bookshelf = [] bookshelf.append("The Effective Engineer") bookshelf.append("The 4 Hour Work Week") print(bookshelf[0]) # The Effective Engineer print(bookshelf[1]) # The 4 Hour Work Week
append
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Dictionary
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dictionary_example = { "key1": "value1", "key2": "value2", "key3": "value3" }
Dictionary
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key
- , value
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dictionary_tk = { "name": "Leandro", "nickname": "Tk", "birthplace": "Brazil" } print("My name is %s" %(dictionary_tk["name"])) # My name is Leandro print("But you can call me %s" %(dictionary_tk["nickname"])) # But you can call me Tk print("And by the way I'm from %s" %(dictionary_tk["birthplace"])) # And by the way I'm from Brazil
dictionary_tk
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Dictionary
- , . age
:
dictionary_tk = { "name": "Leandro", "nickname": "Tk", "birthplace": "Brazil" "age": 24 } print("My name is %s" %(dictionary_tk["name"])) # My name is Leandro print("But you can call me %s" %(dictionary_tk["nickname"])) # But you can call me Tk print("And by the way I'm from %s" %(dictionary_tk["birthplace"])) # And by the way I'm from Brazil
: age
, : 24
, .
, , . , , - , Dictionary. , :
dictionary_tk = { "name": "Leandro", "nickname": "Tk", "birthplace": "Brazil" } dictionary_tk['age'] = 24 print(dictionary_tk) # {'birthplace': 'Brazil', 'age': 24, 'nickname': 'Tk', 'name': 'Leandro'}
. , ?
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:
Python, ( List
) . Python, For
. :
bookshelf = [ "The Effective Engineer", "The 4 hours work week", "Zero to One", "Lean Startup", "Hooked" ] for book in bookshelf: print(book)
- bookshelf
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dictionary = { "some_key": "some_value" } for key in dictionary: print("%s --> %s" %(key, dictionary[key])) # some_key --> some_value
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dictionary = { "some_key": "some_value" } for key, value in dictionary.items(): print("%s --> %s" %(key, value)) # some_key --> some_value
key
value
, . . :
dictionary_tk = { "name": "Leandro", "nickname": "Tk", "birthplace": "Brazil", "age": 24 } for attribute, value in dictionary_tk.items(): print("My %s is %s" %(attribute, value)) # My name is Leandro # My nickname is Tk # My birthplace is Brazil # My age is 24
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Python def
:
def my_function(): print("Hello from a function")
, , :
def my_function(): print("Hello from a function") my_function()
. . , . fname
. , , :
def my_function(fname): print(fname + " Refsnes") my_function("Emil") my_function("Tobias") my_function("Linus")
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def my_function(fname, lname): print(fname + " " + lname) my_function("Emil", "Refsnes")
, , *
.
def my_function(*kids): print("The youngest child is " + kids[2]) my_function("Emil", "Tobias", "Linus")
. , :
def my_function(country = "Norway"): print("I am from " + country) my_function("Sweden") #I am from Sweden my_function() #I am from Norway
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def my_function(food): for x in food: print(x) fruits = ["apple", "banana", "cherry"] my_function(fruits)
, return
:
def my_function(x): return 5 * x print(my_function(3)) #15 print(my_function(5)) #25
Python
Python . , .
Python 3.6 Python 2.7. Python 3.6 input()
.
username = input("Enter username:") print("Username is: " + username)
Python 2.7 raw_input()
.
username = raw_input("Enter username:") print("Username is: " + username)
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try
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except
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finally
try
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try
:
try: print(x) except: print("An exception occurred")
try
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try
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try: print(x) except NameError: print("Variable x is not defined") except: print("Something else went wrong")
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else
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try: print("Hello") except: print("Something went wrong") else: print("Nothing went wrong")
finally
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.
try: print(x) except: print("Something went wrong") finally: print("The 'try except' is finished")
Python .
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x = -1 if x < 0: raise Exception("Sorry, no numbers below zero")
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x = "hello" if not type(x) is int: raise TypeError("Only integers are allowed")
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class Vehicle: pass
pass
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car = Vehicle() print(car) # <__main__.Vehicle instance at 0x7fb1de6c2638>
car
- ( ) Vehicle
.
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class Vehicle: def __init__(self, number_of_wheels, type_of_tank, seating_capacity, maximum_velocity): self.number_of_wheels = number_of_wheels self.type_of_tank = type_of_tank self.seating_capacity = seating_capacity self.maximum_velocity = maximum_velocity
__init__
,
self
.
init
. . , , . , Tesla Model S . , , , 250 /. :
tesla_model_s = Vehicle(4, 'electric', 5, 250)
+ + + 250 /.
. ? . . . :
class Vehicle: def __init__(self, number_of_wheels, type_of_tank, seating_capacity, maximum_velocity): self.number_of_wheels = number_of_wheels self.type_of_tank = type_of_tank self.seating_capacity = seating_capacity self.maximum_velocity = maximum_velocity def number_of_wheels(self): return self.number_of_wheels def set_number_of_wheels(self, number): self.number_of_wheels = number
: number_of_wheels
set_number_of_wheels
. (getter) (setter). , .
Python , @property
() . :
class Vehicle: def __init__(self, number_of_wheels, type_of_tank, seating_capacity, maximum_velocity): self.number_of_wheels = number_of_wheels self.type_of_tank = type_of_tank self.seating_capacity = seating_capacity self.maximum_velocity = maximum_velocity @property def number_of_wheels(self): return self.__number_of_wheels @number_of_wheels.setter def number_of_wheels(self, number): self.__number_of_wheels = number
, :
tesla_model_s = Vehicle(4, 'electric', 5, 250) print(tesla_model_s.number_of_wheels) # 4 tesla_model_s.number_of_wheels = 2 # 2 print(tesla_model_s.number_of_wheels) # 2
. . , , , 2 number_of_wheels
. Python.
, , make_noise. :
class Vehicle: def __init__(self, number_of_wheels, type_of_tank, seating_capacity, maximum_velocity): self.number_of_wheels = number_of_wheels self.type_of_tank = type_of_tank self.seating_capacity = seating_capacity self.maximum_velocity = maximum_velocity def make_noise(self): print('VRUUUUUUUM')
, VRRRRUUUUM.
tesla_model_s = Vehicle(4, 'electric', 5, 250) tesla_model_s.make_noise() # VRUUUUUUUM
:
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non-public
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Python .
class Person: def __init__(self, first_name): self.first_name = first_name
first_name
(public instance variable).
tk = Person('TK') print(tk.first_name) # => TK
:
class Person: first_name = 'TK'
first_name
, , TK
.
tk = Person() print(tk.first_name) # => TK
, . - , . ? : .
Person
, first_name
:
tk = Person('TK') tk.first_name = 'Kaio' print(tk.first_name) # => Kaio
kaio
first_name
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:
class Person: def __init__(self, first_name, email): self.first_name = first_name self._email = email
_email
? :
tk = Person('TK', 'tk@mail.com') print(tk._email) # tk@mail.com
. - , API.
API - . .
, , . (emali
update_email
), :
class Person: def __init__(self, first_name, email): self.first_name = first_name self._email = email def update_email(self, new_email): self._email = new_email def email(self): return self._email
. :
tk = Person('TK', 'tk@mail.com') print(tk.email()) # => tk@mail.com # tk._email = 'new_tk@mail.com' -- API print(tk.email()) # => tk@mail.com tk.update_email('new_tk@mail.com') print(tk.email()) # => new_tk@mail.com
-
TK
tk@mail.com
-
email
, - API.
- !
:
class Person: def __init__(self, first_name, age): self.first_name = first_name self._age = age def show_age(self): return self._age
:
tk = Person('TK', 25) print(tk.show_age()) # => 25
- .
. Person
, show_age
_
.
class Person: def __init__(self, first_name, age): self.first_name = first_name self._age = age def _show_age(self): return self._age
:
tk = Person('TK', 25) print(tk._show_age()) # => 25
. . - , API.
, :
class Person: def __init__(self, first_name, age): self.first_name = first_name self._age = age def show_age(self): return self._get_age() def _get_age(self): return self._age tk = Person('TK', 25) print(tk.show_age()) # => 25
_get_age
show_age
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( ), _get_age
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). : .
, .
:
: .
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Python.
. , - . , ElectricCar
Car
.
class Car: def __init__(self, number_of_wheels, seating_capacity, maximum_velocity): self.number_of_wheels = number_of_wheels self.seating_capacity = seating_capacity self.maximum_velocity = maximum_velocity
Car
:
my_car = Car(4, 5, 250) print(my_car.number_of_wheels) print(my_car.seating_capacity) print(my_car.maximum_velocity)
. .
Python (parent) (child) . ElectricCar
Car
.
class ElectricCar(Car): def __init__(self, number_of_wheels, seating_capacity, maximum_velocity): Car.__init__(self, number_of_wheels, seating_capacity, maximum_velocity)
. - , ( Car). :
my_electric_car = ElectricCar(4, 5, 250) print(my_electric_car.number_of_wheels) # => 4 print(my_electric_car.seating_capacity) # => 5 print(my_electric_car.maximum_velocity) # => 250
Python
? , - , . , , .
, .py
:
mymodule.py
def greeting(name): print("Hello, " + name)
, import
:
import mymodule mymodule.greeting("Jonathan") #Hello, Jonathan
, as
:
import mymodule as mx
Python , .
import platform x = platform.system() print(x)
( ) . dir()
:
import platform x = dir(platform) print(x)
:
['DEV_NULL', '_UNIXCONFDIR', 'WIN32_CLIENT_RELEASES', 'WIN32_SERVER_RELEASES', '__builtins__', '__cached__', '__copyright__', '__doc__', '__file__', '__loader__', '__name__', '__package __', '__spec__', '__version__', '_default_architecture', '_dist_try_harder', '_follow_symlinks', '_ironpython26_sys_version_parser', '_ironpython_sys_version_parser', '_java_getprop', '_libc_search', '_linux_distribution', '_lsb_release_version', '_mac_ver_xml', '_node', '_norm_version', '_perse_release_file', '_platform', '_platform_cache', '_pypy_sys_version_parser', '_release_filename', '_release_version', '_supported_dists', '_sys_version', '_sys_version_cache', '_sys_version_parser', '_syscmd_file', '_syscmd_uname', '_syscmd_ver', '_uname_cache', '_ver_output', 'architecture', 'collections', 'dist', 'java_ver', 'libc_ver', 'linux_distribution', 'mac_ver', 'machine', 'node', 'os', 'platform', 'popen', 'processor', 'python_branch', 'python_build', 'python_compiler', 'python_implementation', 'python_revision', 'python_version', 'python_version_tuple', 're', 'release', 'subprocess', 'sys', 'system', 'system_aliases', 'uname', 'uname_result', 'version', 'warnings', 'win32_ver']
Python
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Python open()
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open()
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t
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f = open("demofile.txt")
, :
f = open("demofile.txt", "rt")
r
t
, .
, , , Python:
, open()
. open()
, read()
:
f = open("demofile.txt", "r") print(f.read())
, , :
f = open("D:\\myfiles\welcome.txt", "r") print(f.read())
, readline()
:
f = open("demofile.txt", "r") print(f.readline())
. - , , , .
f = open("demofile.txt", "r") print(f.readline()) f.close()
open()
:
a
- -w
- -
"demofile2.txt" :
f = open("demofile2.txt", "a") f.write("Now the file has more content!") f.close() # : f = open("demofile2.txt", "r") print(f.read())
"demofile3.txt" :
f = open("demofile3.txt", "w") f.write("Woops! I have deleted the content!") f.close()
Python, open()
:
x
- - , ,a
- - ,w
- - ,
myfile.txt
:
f = open ("myfile.txt", "x")
: !
, os
os.remove()
:
import os os.remove("demofile.txt")
, , , :
import os if os.path.exists("demofile.txt"): os.remove("demofile.txt") else: print("The file does not exist")
, os.rmdir()
:
import os os.rmdir("myfolder")
.
Python PIP
PIP? PIP - Python , .
. Python 3.4 , PIP .
? , . - Python, .
, PIP
Python :
C:\Users\Your Name\AppData\Local\Programs\Python\Python36-32\Scripts>pip --version
PIP
PIP, : https://pypi.org/project/pip/
. PIP . Python :
C:\Users\Your Name\AppData\Local\Programs\Python\Python36-32\Scripts>pip install camelcase
camelcase
. camelcase import
.
import camelcase c = camelcase.CamelCase() txt = "hello world" print(c.hump(txt))
uninstall
, :
C:\Users\Your Name\AppData\Local\Programs\Python\Python36-32\Scripts>pip uninstall camelcase
PIP , :
Uninstalling camelcase-02.1: Would remove: c:\users\Your Name\appdata\local\programs\python\python36-32\lib\site-packages\camecase-0.2-py3.6.egg-info c:\users\Your Name\appdata\local\programs\python\python36-32\lib\site-packages\camecase\* Proceed (y/n)?
y
, .
list
, , :
C:\Users\Your Name\AppData\Local\Programs\Python\Python36-32\Scripts>pip list
Package Version ----------------------- camelcase 0.2 mysql-connector 2.1.6 pip 18.1 pymongo 3.6.1 setuptools 39.0.1
!
Python:
- Python
- Python
- Python
- Python (while for)
- Python
- Python
- Python
- Python
- Python
- PIP
- :
- Dictionary
- Python
- :
- :