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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def download(self, project, filename, targetfilename, loadmetadata=None):
 """Download an output file"""

        if loadmetadata is None: loadmetadata = self.loadmetadata
        f = clam.common.data.CLAMOutputFile(self.url + project,  filename, loadmetadata, self)
        f.copy(targetfilename)