ref: https://stackoverflow.com/questions/748675/finding-duplicate-files-and-removing-them

remove_dup.py

#!/usr/bin/env python2
import sys
import os
import hashlib


def chunk_reader(fobj, chunk_size=1024):
    """Generator that reads a file in chunks of bytes"""
    while True:
        chunk = fobj.read(chunk_size)
        if not chunk:
            return
        yield chunk


def get_hash(filename, first_chunk_only=False, hash=hashlib.sha1):
    hashobj = hash()
    file_object = open(filename, 'rb')

    if first_chunk_only:
        hashobj.update(file_object.read(1024))
    else:
        for chunk in chunk_reader(file_object):
            hashobj.update(chunk)
    hashed = hashobj.digest()

    file_object.close()
    return hashed


def check_for_duplicates(paths, hash=hashlib.sha1):
    hashes_by_size = {}
    hashes_on_1k = {}
    hashes_full = {}
    ret = []

    for path in paths:
        for dirpath, dirnames, filenames in os.walk(path):
            for filename in filenames:
                full_path = os.path.join(dirpath, filename)
                try:
                    # if the target is a symlink (soft one), this will
                    # dereference it - change the value to the actual target file
                    full_path = os.path.realpath(full_path)
                    file_size = os.path.getsize(full_path)
                except (OSError,):
                    # not accessible (permissions, etc) - pass on
                    continue

                duplicate = hashes_by_size.get(file_size)

                if duplicate:
                    hashes_by_size[file_size].append(full_path)
                else:
                    hashes_by_size[file_size] = []  # create the list for this file size
                    hashes_by_size[file_size].append(full_path)

    # For all files with the same file size, get their hash on the 1st 1024 bytes
    for __, files in hashes_by_size.items():
        if len(files) < 2:
            continue    # this file size is unique, no need to spend cpy cycles on it

        for filename in files:
            try:
                small_hash = get_hash(filename, first_chunk_only=True)
            except (OSError,):
                # the file access might've changed till the exec point got here
                continue

            duplicate = hashes_on_1k.get(small_hash)
            if duplicate:
                hashes_on_1k[small_hash].append(filename)
            else:
                hashes_on_1k[small_hash] = []          # create the list for this 1k hash
                hashes_on_1k[small_hash].append(filename)

    # For all files with the hash on the 1st 1024 bytes, get their hash on the full file - collisions will be duplicates
    for __, files in hashes_on_1k.items():
        if len(files) < 2:
            continue    # this hash of fist 1k file bytes is unique, no need to spend cpy cycles on it

        for filename in files:
            try:
                full_hash = get_hash(filename, first_chunk_only=False)
            except (OSError,):
                # the file access might've changed till the exec point got here
                continue

            duplicate = hashes_full.get(full_hash)
            if duplicate:
                print "Duplicate found: %s and %s" % (filename, duplicate)
                ret.append(filename)
            else:
                hashes_full[full_hash] = filename
    return ret

def check_dir(paths):
    print '=====>', paths
    ret = check_for_duplicates(paths)
    print ret

    if len(ret) > 0:
        print 'remove those file? [Y/N]'
        choice = raw_input().lower()
        if choice == 'y':
            for i in ret:
                os.remove(i)
            print 'removed'

if sys.argv[1:]:
    for i in sys.argv[1:]:
        check_dir([i])
else:
    print "Please pass the paths to check as parameters to the script"