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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 setup_fields(attrs):
 """ Collect all fields declared on the class and remove them from attrs """

    fields = {}
    iterator = list(attrs.items())
    for key, value in iterator:
        if not isinstance(value, Field):
            continue
        fields[key] = value
        del attrs[key]
    return fields