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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 from_object(obj):
 """ Convert an object representing a contact information to an instance `Contact`. @param obj: an object containg the following attributes: * `name`: an item of the enumeration `ContactName` representing the type of this contact information. * `value`: value of this contact information representing by a string, such as ``+84.01272170781``, the formatted value for a telephone number property. * `is_primary`: indicate whether this contact property is the first to be used to contact the entity that this contact information corresponds to. There is only one primary contact property for a given property name (e.g., `EMAIL`, `PHONE`, `WEBSITE`). * `is_verified`: indicate whether this contact information has been verified, whether it has been grabbed from a trusted Social Networking Service (SNS), or whether through a challenge/response process. @raise ValueError: if the value of this contact information is null. """

        return obj if isinstance(obj, Contact) \
            else Contact(cast.string_to_enum(obj.name, Contact.ContactName),
                         obj.value,
                         is_primary=obj.is_primary and cast.string_to_boolean(obj.is_primary, strict=True),
                         is_verified=obj.is_verified and cast.string_to_boolean(obj.is_verified, strict=True))