Day 22: Python Shortcuts to write Cleaner and more Efficient Code

1. List Comprehensions

# Instead of 
squares = [ ]
for i in range(10):
    squares.append(i**2)

#Use
squares = [ i**2 for i in range(10)]        

2. Dictionary Comprehensions

# Instead of
squares_dict = {}
for i in range(10):
    squares_dict[i] = i**2

# Use
squares_dict = { i : i**2 for i in range(10)}        

3. Multiple Assignments

# Instead of 
a=1
b=2
c=3

#Use
a, b, c = 1, 2, 3        

4. String Join

# Instead of:
words = ['Python', 'is', 'awesome']
sentence = ''
for word in words:
    sentence += word+' '

#Use
sentence = ' '.join(words)        

5. Conditional Expressions (Ternary Operator)

# Instead of
if condition:
    x = a
else:
    x = b

#Use
x = a if condition else b        

6. Use of enumerate for Index

# Instead of 
index = 0
for item in items:
    print(index, item)
    index +=1

# Use
for index, item in enumerate(items):
    print(index, item)        

7. Zip for Parallel Iteration

# Instead of:
for i in range(len(list1)):
    print(list1[i], list2[i])

#Use
for item1, item2 in zip(list1,list2):
    print(item1, item2)        

8. all and any

# Instead of
for item in items:
    if not condition(item):
        check = False
        break

# Use
check = all(condition(item) for item in items)        

9. Context Managers (with statement)

# Instead of
file = open('file.txt','r')
try:
    content = file.read()
finally:
    file.close()

#Use
with open('file.txt','r') as file:
    content = file.read()        

10. get Method for Dictionaries

#Instead of
if key in dict:
    value = dict[key]
else:
    value = default

# Use
value = dict.get(key, default)        

#Python #100DaysOfCode #Shortcuts