import numpy as np
class test_data:
    def __init__(self,n_samples,dim):
        class generate:
            def __init__(self,n_samples,dim):
                self.n_samples = n_samples
                self.dim = dim
                self.mu = 0.0
                self.sigma = 0.0

            def mu_sigma(self):
                self.mu = np.random.uniform(low=-2.0, high=2.0, size=self.dim)
                self.sigma = np.random.uniform(low=1.0, high=2.0, size=self.dim)

        self.n_samples = n_samples
        self.dim = dim
        self.generate = generate(n_samples,dim)
        self.generate.mu_sigma()
        self.mu = self.generate.mu
        self.sigma = self.generate.sigma

data=test_data(n_samples=10,dim=2)
print(data.generate.mu)
print(data.mu)