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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 import_file(filename, name=None):
 """ Imports a module from a single file as if it doesn't belong to a particular package. The returned module will have the optional ``name`` if given, or else a name generated from the filename. """

    # Specifying a traditional dot-separated fully qualified name here
    # results in a number of "Parent module 'astropy' not found while
    # handling absolute import" warnings.  Using the same name, the
    # namespaces of the modules get merged together.  So, this
    # generates an underscore-separated name which is more likely to
    # be unique, and it doesn't really matter because the name isn't
    # used directly here anyway.
    mode = 'r'

    if name is None:
        basename = os.path.splitext(filename)[0]
        name = '_'.join(os.path.relpath(basename).split(os.sep)[1:])

    if not os.path.exists(filename):
        raise ImportError('Could not import file {0}'.format(filename))

    if import_machinery:
        loader = import_machinery.SourceFileLoader(name, filename)
        mod = loader.load_module()
    else:
        with open(filename, mode) as fd:
            mod = imp.load_module(name, fd, filename, ('.py', mode, 1))

    return mod