Series

x = Series(
    ['a', True, 1]
)

x = Series(
    ['a', True, 1], 
index=['first', 'second', 'third']    
)
Precautions:
1. Access: Access based on location. Accessed from "0".
2. Access according to the index. x['second']
3. No cross-border access
4. In a sequence, a single factor cannot be added.
  eg:a.append('2') is an error.
  Correct spelling:
  n=Series(['2'])，x.append(n)
5. A variable is required to carry the change of the variable
    x=x.append(n)

6. Determine if an element is in it:
     '2' in x
7. Deletion of sequences:
   #1 Delete by index:
        x.drop('first')
   #2 Delete by index position
        x.drop(x.index[3])
8、x['2'!=x.values]