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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 scan_file(path):
 """ Scan `path` for viruses using ``clamscan`` program. Args: path (str):
 Relative or absolute path of file/directory you need to scan. Returns: dict: ``{filename: ("FOUND", "virus type")}`` or blank dict. Raises: AssertionError: When the internal file doesn't exists. """

    path = os.path.abspath(path)
    assert os.path.exists(path), "Unreachable file '%s'." % path

    result = sh.clamscan(path, no_summary=True, infected=True, _ok_code=[0, 1])

    return _parse_result(result)