Python - Find line number from text file [closed]

Answer 1

with open('test.txt') as f:
    content = f.readlines()

index = [x for x in range(len(content)) if 'pizza' in content[x].lower()]

Part (1) of the code reads each line as a separate list in variable "content".

Part (2) populates out the line # of content only if 'pizza' exists in that line. [x for x in range(len(content))] simply populates all index values, while 'if 'pizza' in content[x].lower()' keeps the line # that matches the string.