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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 _estimate_angle(angle, reg_coordinate_frame, header):
 """Transform an angle into a different frame Parameters angle : float, int The number of degrees, measured from the Y axis in origin's frame reg_coordinate_frame : str Coordinate frame in which ``angle`` is defined header : `~astropy.io.fits.Header` instance Header describing the image Returns ------- angle : float The angle, measured from the Y axis in the WCS defined by ``header'` """

    y_axis_rot = _calculate_rotation_angle(reg_coordinate_frame, header)
    return angle - y_axis_rot