import sys,os

kilobytes = 1024

megabytes = kilobytes*1000

chunksize = int(200*megabytes)#default chunksize

def split(fromfile,todir,chunksize=chunksize):

    if not os.path.exists(todir):#check whether todir exists or not

        os.mkdir(todir)

    else:

        for fname in os.listdir(todir):

            os.remove(os.path.join(todir,fname))

    partnum = 0

    inputfile = open(fromfile,'rb')#open the fromfile

    while True:

        chunk = inputfile.read(chunksize)

        if not chunk:             #check the chunk is empty

            break

        partnum += 1

        filename = os.path.join(todir,('data%04d'%partnum))

        fileobj = open(filename,'wb')#make partfile

        fileobj.write(chunk)         #write data into partfile

        fileobj.close()

    return partnum

if __name__=='__main__':

        fromfile  = input('File to be split?')

        todir     = input('Directory to store part files?')

        chunksize = int(input('Chunksize to be split?'))

        absfrom,absto = map(os.path.abspath,[fromfile,todir])

        print('Splitting',absfrom,'to',absto,'by',chunksize)

        try:

            parts = split(fromfile,todir,chunksize)

        except:

            print('Error during split:')

            print(sys.exc_info()[0],sys.exc_info()[1])

        else:

            print('split finished:',parts,'parts are in',absto)