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$ python3 hello_world.py

• 변수 이름은 snake_case로
• 문자열은 “This is a string”, 'This is also a string.' 모두 가능
• {string_variable}.title() → 첫 글자 대문자로
• {string_variable}.upeer()
• {string_variable}.lower()
• f-string
  • full_name = f“{first_name} {last_name}”
  • full_name = “{} {}”.format(fist_name, last_name)
• escape characters; \', \\, \n, \r, \t, \b, \f, \ooo, \xhh
• {string_variable}.rstrip() → 오른쪽 공백 삭제, .strip() → 양쪽 공백 제거, .lstrip() → 왼쪽 공백 제거
• numeric; integer, floating point number, underscored number → 15_000_000_000
• 상수는 대문자로; MAX_CONNECTIONS = 5000
• comments; #

message = "Hello Python"
print(message)

>>> import this

• 대괄호 []와 콤마 ,
• 이름을 복수형으로
• 인덱스는 0부터, [-1]은 끝에서부터의 인덱스

bicycles = ['trek', 'cannondale', 'redline', 'specialized']
print(bicycles)

print(bicycles[0])
print(bicycles[0].title())

bicycles[0] = 'mini bell'  # change value
bicycles.append('trek')  # append value
bicycles.insert(0, 'strida')  # insert value

del bicycles[0]  # delete
popped_bicycle = bicycles.pop()  # pop value (stack)
#popped_bicycle = bicycles.pop(0)  # pop value by index
bicycles.remove('redline')  # remove by value

bicycles.sort()  # sort permanently by alphabet
bicycles.sort(reverse=True) # reverse sort
print(sorted(bicycles))  # sort temporarily
bicycles.reverse()  #

len(bicycles)
 

magicians = ['alice', 'david', 'carolina']
for magician in magicians:
    print(magician)
    
for value in range(1, 5):  # 1 ~ 4
    print(value)
    
numbers = list(range(1, 6))  # numbers = [1, 2, 3, 4, 5]
even_numbers = list(range(2, 11, 2))  # even_numbers = [2, 4, 6, 8, 10]

squares = []
for value in range(1, 11):
    square = value ** 2
    squares.appen(square)
# squares = [value ** 2 for value in range(1,11)]
print(squares)

digits = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
min(digits)
max(digits)
sum(digits)

• slice; 원래 리스트 유지
  • players[0:3] # index 0에서부터 3개까지 자름 [:3]
  • players[2:] # index 2부터 끝까지
  • players[-3:] # 끝에서 셋
• 복사
  • my_friends = your_friends[:]
  • my_friends = your_friends는 포인터 같은 역할
• tuple(immutable)
  • 대괄호 대신 소괄호 ()와 콤마 ,
  • 한 개 항목의 튜플이더라도 콤마 필요; my_t = (3,)

• Coding style; PEP(Python Enhancement Proposal) 8
  • 들여쓰기 공백 네 칸
  • 행 길이 79자
  • PEP 8 -- Style Guide for Python Code