python file open

with open("file.txt") as file_in:
    lines = []
    for line in file_in:
        lines.append(line)

with open('pagehead.section.htm','r') as f:
    output = f.read()

f = open("test.txt", mode='r', encoding='utf-8')

# Open function to open the file "MyFile1.txt" 
# (same directory) in append mode and
file1 = open("MyFile.txt","a")
  
# store its reference in the variable file1 
# and "MyFile2.txt" in D:\Text in file2
file2 = open(r"D:\Text\MyFile2.txt","w+")