Project1 python

from pathlib import Path
import os.path
import shutil

def get_filename_D(input_path: str) -> list:
    '''Return a list of files
    with a given path'''
    list_file = []
    for run in input_path.iterdir():
        if run.is_file():
            list_file.append(run)
    return list_file
def get_dir_R(input_path: str) -> list:
    '''return a list of directory path
    with a given path'''
    list_dir = []
    for run in input_path.iterdir():
        if run.is_dir():
            list_dir.append(run)
    return list_dir
def get_filename_R(input_path: str) -> list:
    '''return a list files in a directory
    and also files inside sub-directories
    and so on'''
    list_file = []
    list_dir = []
    list_file += get_filename_D(input_path)
    list_dir += get_dir_R(input_path)
    for run in list_dir:
        list_file += get_filename_R(run)
    return list_file

def print_filename(list_of_path: list) -> str:
    '''convert a list of path into string
    and print out the string'''
    for n in list_of_path:
        print(n)
def second_input_a(list_of_path: list) -> list:
    '''from a given list of files, return a
    list of files that is exactly the same'''
    file_interesting = []
    for n in list_of_path:
        file_interesting.append()
    return file_interesting

def second_input_n(list_of_path: list, name_input: str) -> list:
    '''from a given list of files, return
    a new list of files that has the same
    filename as the one that user inputs'''
    file_interesting = []
    for n in list_of_path:
        if os.path.split(n)[1] == name_input:
            file_interesting.append(n)
    return file_interesting

def second_input_e(list_of_path: list, name_input: str):
    '''from a given list of files, return
    a new list of files that has the same
    extention as the one that user inputs'''
    file_interesting = []
    for n in list_of_path:
        if os.path.splitext(n)[1] == name_input or os.path.splitext(n)[1][1:] == name_input:
            file_interesting.append(n)
    return file_interesting
def second_input_t(list_of_path: list, keyword: str) -> list:
    '''from a given list of files, return
    a new list of  text files that contains
    a string same as user input'''
    file_interesting = []
    for n in list_of_path:
        try:
            the_file = open(n)
            while True:
                line = the_file.readline()
                if line.find(keyword) != -1:
                    file_interesting.append(n)
                if line == '':
                    break
        except ValueError:
            pass
        finally:
            if the_file != None:
                the_file.close()
    return file_interesting
def second_input_smaller(list_of_path: list,name_input: str) -> list:
    '''from a given list of files, return a sublist
    of files whose size is smaller than user input'''
    file_interesting = []
    for n in list_of_path:
        if os.path.getsize(n) < int(name_input):
            file_interesting.append(n)
    return file_interesting

def second_input_greater(list_of_path: list,name_input: str) -> list:
    '''from a given list of files, return a sublist
    of files whose size is greater than user input'''
    file_interesting = []
    for n in list_of_path:
        if os.path.getsize(n) > int(name_input):
            file_interesting.append(n)
    return file_interesting

def third_input_f(list_of_path: list) -> str:
    '''from a list of files, print the first line if
    the file is text, and print 'NOT TEXT' if the file
    is not a text file'''
    for n in list_of_path:
        try:
            the_file = open(n)
            line = the_file.readline().strip()
            if line != '':
                print(line)
                the_file.close()
            else:
                print(line)
                the_file.close()
        except ValueError:
            print('NOT TEXT')
def third_input_dup(list_of_path: list) -> None:
    '''from a list of files, duplicate every file, and
    store it in the same directory'''
    for n in list_of_path:
        string = str(n)
        shutil.copy2(string, string + '.dup')
def the_first_input():
    while True:
        first_input = input()
        path1 = Path(first_input[2:])
        if path1.is_dir():
            if first_input.startswith('D '):
                file_list = get_filename_D(path1)
                print_filename(file_list)
                return file_list
            elif first_input.startswith('R '):
                file_list = get_filename_R(path1)
                print_filename(file_list)
                return file_list
            else:
                print('Error')
        else:
            print('ERROR')
def the_second_input(filez_list):
    list_of_interesting = []
    while True:
        second_input = input()
        name_of_file = second_input[2:]
        code = second_input[:2]
        if second_input.strip() == 'A':
            list_of_interesting = filez_list
            print_filename(list_of_interesting)
            return list_of_interesting
        elif code == 'N ':
            print_filename(second_input_n(filez_list,name_of_file))
            list_of_interesting = second_input_n(filez_list,name_of_file)
            return list_of_interesting
        elif code == 'E ' :
            print_filename(second_input_e(filez_list,name_of_file))
            list_of_interesting = second_input_e(filez_list,name_of_file)
            return list_of_interesting
        elif code == 'T ':
            print_filename(second_input_t(filez_list,name_of_file))
            list_of_interesting = second_input_t(filez_list,name_of_file)
            return list_of_interesting
        elif code == '< ':
            try:
                print_filename(second_input_smaller(filez_list,name_of_file))
                list_of_interesting = second_input_smaller(filez_list,name_of_file)
                return list_of_interesting
            except ValueError:
                print('ERROR')

        elif code == '> ':
            try:
                print_filename(second_input_greater(filez_list,name_of_file))
                list_of_interesting = second_input_greater(filez_list,name_of_file)
                return list_of_interesting
            except ValueError:
                print('ERROR')
        else:
            print('ERROR')
def the_third_input(file_list):
    while True:
        third_input = input()
        if third_input == 'F':
            third_input_f(file_list)
            return True
        elif third_input == 'D':
            third_input_dup(file_list)
            return True
        else:
            print('ERROR')


def the_whole_puzzle():
    file_list = the_first_input()
    interesting_file_list = the_second_input(file_list)
    the_third_input(interesting_file_list)

the_whole_puzzle()