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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 dump_cml(f, molecules):
 """Write a list of molecules to a CML file Arguments: | ``f`` -- a filename of a CML file or a file-like object | ``molecules`` -- a list of molecule objects. """

    if isinstance(f, str):
        f = open(f, "w")
        close = True
    else:
        close = False
    f.write("<?xml version='1.0'?>\n")
    f.write("<list xmlns='http://www.xml-cml.org/schema'>\n")
    for molecule in molecules:
        _dump_cml_molecule(f, molecule)
    f.write("</list>\n")
    if close:
        f.close()