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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_cap(cls, theta, lmax, clat=None, clon=None, nmax=None, theta_degrees=True, coord_degrees=True, dj_matrix=None):
 """ Construct spherical cap Slepian functions. Usage ----- x = Slepian.from_cap(theta, lmax, [clat, clon, nmax, theta_degrees, coord_degrees, dj_matrix]) Returns ------- x : Slepian class instance Parameters theta : float Angular radius of the spherical-cap localization domain (default in degrees). lmax : int Spherical harmonic bandwidth of the Slepian functions. clat, clon : float, optional, default = None Latitude and longitude of the center of the rotated spherical-cap Slepian functions (default in degrees). nmax : int, optional, default (lmax+1)**2 Number of Slepian functions to compute. theta_degrees : bool, optional, default = True True if theta is in degrees. coord_degrees : bool, optional, default = True True if clat and clon are in degrees. dj_matrix : ndarray, optional, default = None The djpi2 rotation matrix computed by a call to djpi2. """

        if theta_degrees:
            tapers, eigenvalues, taper_order = _shtools.SHReturnTapers(
                _np.radians(theta), lmax)
        else:
            tapers, eigenvalues, taper_order = _shtools.SHReturnTapers(
                theta, lmax)

        return SlepianCap(theta, tapers, eigenvalues, taper_order, clat, clon,
                          nmax, theta_degrees, coord_degrees, dj_matrix,
                          copy=False)