python_grep_function.py

def grep(text, match, after=0, before=0):
    """
    Return matched lines in given text as a list. Similar to grep function but a simple one.
    """
    idx = []
    lines = text.split("\n")
    
    for i, line in enumerate(lines):
        if str(match) not in line:
            continue

        idx.append(i)
        if after:
            idx += range(i + 1, i + 1 + after)
        if before:
            idx += range(i - before, i)

    idx = sorted(list(set(idx)))
    
    return [lines[i] for i in idx]