






'''simple docstring'''




from __future__ import annotations







def       __UpperCAmelCase						(  lowerCamelCase_)							->     None:
		create_state_space_tree(lowerCamelCase_     ,      []     ,      0     ,      [0 for i in range(len(lowerCamelCase_))])







def       __UpperCAmelCase						(  lowerCamelCase_     ,      lowerCamelCase_     ,      lowerCamelCase_     ,      lowerCamelCase_     ,      )							->     None:

		if index == len(lowerCamelCase_):
				print(lowerCamelCase_)
				return

		for i in range(len(lowerCamelCase_)):
				if not index_used[i]:
						current_sequence.append(sequence[i])
						UpperCamelCase__				:					List[str]					=					True
						create_state_space_tree(lowerCamelCase_     ,      lowerCamelCase_     ,      index + 1     ,      lowerCamelCase_)
						current_sequence.pop()
						UpperCamelCase__				:					Dict					=					False
lowerCAmelCase__          =						[3, 1, 2, 4]
generate_all_permutations(sequence)

lowerCAmelCase__          =						["A", "B", "C"]


generate_all_permutations(sequence_a)












'''simple docstring'''




from math import log

from scipy.constants import Boltzmann, physical_constants

lowerCAmelCase__          =						300  # TEMPERATURE (unit = K)







def       __UpperCAmelCase						(  lowerCamelCase_     ,      lowerCamelCase_     ,      lowerCamelCase_     ,      )							->     float:

		if donor_conc <= 0:
				raise ValueError('Donor concentration should be positive')
		elif acceptor_conc <= 0:
				raise ValueError('Acceptor concentration should be positive')
		elif intrinsic_conc <= 0:
				raise ValueError('Intrinsic concentration should be positive')
		elif donor_conc <= intrinsic_conc:
				raise ValueError(
				    'Donor concentration should be greater than intrinsic concentration')
		elif acceptor_conc <= intrinsic_conc:
				raise ValueError(
				    'Acceptor concentration should be greater than intrinsic concentration')
		else:
				return (
				    Boltzmann
				    * T
				    * log((donor_conc * acceptor_conc) / intrinsic_conc**2)
				    / physical_constants["electron volt"][0]
				)


if __name__ == "__main__":
		import doctest

		doctest.testmod()




