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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 volume_create(self, name, size=100, snapshot=None, voltype=None,
                      availability_zone=None):
        '''
        Create a block device
        '''
        if self.volume_conn is None:
            raise SaltCloudSystemExit('No cinder endpoint available')
        nt_ks = self.volume_conn
        response = nt_ks.volumes.create(
            size=size,
            display_name=name,
            volume_type=voltype,
            snapshot_id=snapshot,
            availability_zone=availability_zone
        )

        return self._volume_get(response.id)