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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 enrollment_identity(self, enrollment_identity):
 """ Sets the enrollment_identity of this EnrollmentId. Enrollment identity. :param enrollment_identity: The enrollment_identity of this EnrollmentId. :type: str """

        if enrollment_identity is None:
            raise ValueError("Invalid value for `enrollment_identity`, must not be `None`")
        if enrollment_identity is not None and not re.search('^A-[A-Za-z0-9:]{95}$', enrollment_identity):
            raise ValueError("Invalid value for `enrollment_identity`, must be a follow pattern or equal to `/^A-[A-Za-z0-9:]{95}$/`")

        self._enrollment_identity = enrollment_identity