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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 validate(name=DEFAULT, all_names=False):
 """Validate all registered keys after loading configuration. Missing values or values which do not pass validation raise :class:`staticconf.errors.ConfigurationError`. By default only validates the `DEFAULT` namespace. :param name: the namespace to validate :type name: string :param all_names: if True validates all namespaces and ignores `name` :type all_names: boolean """

    for namespace in get_namespaces_from_names(name, all_names):
        all(value_proxy.get_value() for value_proxy in namespace.get_value_proxies())