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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 find_class(name, classes):
 """Return class in ``classes`` identified by configuration key ``name``."""

    name = name.lower()
    cls = next((c for c in classes if c.configuration_key == name), None)
    if cls is None:
        raise ValueError("No class named '%s' could be found" % name)
    return cls