def reset_dq_bits(input,bits,extver=None,extname='dq'):
    """ This function resets bits in the integer array(s) of a FITS file.

    Parameters
    ----------
    filename : str
        full filename with path

    bits : str
        sum or list of integers corresponding to all the bits to be reset

    extver : int, optional
        List of version numbers of the DQ arrays
        to be corrected [Default Value: None, will do all]

    extname : str, optional
        EXTNAME of the DQ arrays in the FITS file
        [Default Value: 'dq']

    Notes
    -----
    The default value of None for the 'extver' parameter specifies that all
    extensions with EXTNAME matching 'dq' (as specified by the 'extname'
    parameter) will have their bits reset.

    Examples
    --------
        1. The following command will reset the 4096 bits in all
           the DQ arrays of the file input_file_flt.fits::

                reset_dq_bits("input_file_flt.fits", 4096)

        2. To reset the 2,32,64 and 4096 bits in the second DQ array,
           specified as 'dq,2', in the file input_file_flt.fits::

                reset_dq_bits("input_file_flt.fits", "2,32,64,4096", extver=2)

    """
    # Interpret bits value
    bits = interpret_bit_flags(bits)

    flist, fcol = parseinput.parseinput(input)
    for filename in flist:
        # open input file in write mode to allow updating the DQ array in-place
        p = fits.open(filename, mode='update', memmap=False)

        # Identify the DQ array to be updated
        # If no extver is specified, build a list of all DQ arrays in the file
        if extver is None:
            extver = []
            for hdu in p:
                # find only those extensions which match the input extname
                # using case-insensitive name comparisons for 'extname'
                if 'extver' in hdu.header and \
                   hdu.header['extname'].lower() == extname.lower():
                    extver.append(int(hdu.header['extver']))
        else:
            # Otherwise, insure that input extver values are a list
            if not isinstance(extver, list): extver = [extver]

        # for each DQ array identified in the file...
        for extn in extver:
            dqarr = p[extname,extn].data
            dqdtype = dqarr.dtype
            # reset the desired bits
            p[extname,extn].data = (dqarr & ~bits).astype(dqdtype) # preserve original dtype
            log.info('Reset bit values of %s to a value of 0 in %s[%s,%s]' %
                     (bits, filename, extname, extn))
        # close the file with the updated DQ array(s)
        p.close()