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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 _index_files(path):
 """Search zip file for SID PHA files"""

        with zipfile.ZipFile(path) as zf:
            names = sorted(zf.namelist())
            names = [nn for nn in names if nn.endswith(".tif")]
            names = [nn for nn in names if nn.startswith("SID PHA")]
            phasefiles = []
            for name in names:
                with zf.open(name) as pt:
                    fd = io.BytesIO(pt.read())
                    if SingleTifPhasics.verify(fd):
                        phasefiles.append(name)
            return phasefiles