Retrieves all the FASTQ files in project self.dx_project_name as DXFile objects.
  
        Args:
            barcode: `str`. If set, then only FASTQ file properties for FASTQ files having the specified barcode are returned.
  
        Returns: 
            `list` of DXFile objects representing FASTQ files.
  
        Raises:
            `dnanexus_utils.FastqNotFound`: No FASTQ files were found.

def get_fastq_dxfile_objects(self,barcode=None):
        """
        Retrieves all the FASTQ files in project self.dx_project_name as DXFile objects.
  
        Args:
            barcode: `str`. If set, then only FASTQ file properties for FASTQ files having the specified barcode are returned.
  
        Returns: 
            `list` of DXFile objects representing FASTQ files.
  
        Raises:
            `dnanexus_utils.FastqNotFound`: No FASTQ files were found.
        """
        fq_ext_glob = "*{}".format(self.FQEXT)
        name = fq_ext_glob
        if barcode:
            name = "*_{barcode}_*{FQEXT}".format(barcode=barcode, FQEXT=self.FQEXT)
        fastqs= dxpy.find_data_objects(project=self.dx_project_id,folder=self.DX_FASTQ_FOLDER,name=name,name_mode="glob")
        if not fastqs:
            # Then look for them in all folders:
            fastqs= dxpy.find_data_objects(project=self.dx_project_id,name=name,name_mode="glob")
           
        if not fastqs:
            msg = "No FASTQ files found for run {run} ".format(run=proj_name)
            if barcode:
                msg += "and barcode {barcode}.".format(barcode=barcode)
            raise FastqNotFound(msg)
        fastqs = [dxpy.DXFile(project=x["project"],dxid=x["id"]) for x in fastqs]
        return fastqs