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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 includeme(config):
 """ Set up event subscribers. """

    from .models import (
        AuthUserMixin,
        random_uuid,
        lower_strip,
        encrypt_password,
    )
    add_proc = config.add_field_processors
    add_proc(
        [random_uuid, lower_strip],
        model=AuthUserMixin, field='username')
    add_proc([lower_strip], model=AuthUserMixin, field='email')
    add_proc([encrypt_password], model=AuthUserMixin, field='password')