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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Physique
Mini Table of Contents
Create or refresh data files
Using Physique from a working directory not containing Physique itself
NIST Fundamental Constants
NIST Official Conversions (to metric) 
Webscraping example
Step1:  NIST Fundamental Constants
Step2:  Find a Fundamental Constant you are interested in using the usual panda modules
Step3:  NIST Official Conversions (to metric)
This is the pandas DataFrame containing all the NIST Official Conversions to SI.
Step4:  From the list of columns, search for the quantity you desired by trying out different search terms
Step5:  Or we can look up the SI unit we want to convert to.
Step6:  Look at what you want and see the index; it happens to be 340 in this example.
Step7:  Then the attributes can accessed by the column names.
Step8:  So for example, the reusable SSME delivers a vacuum thrust of 470000 lb or
Step9:  To obtain the conversion for pressure in psia, which we search for with "psi"
Step10:  So for a chamber pressure of 3028 psia for the SSME,
Step11:  Also, get the conversion for atmospheres (atm)
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Python Code:
import os
print(os.getcwd())
os.chdir(os.getcwd() + "/Physique/") # change current working directory
print(os.getcwd())
%run -i ./Scripts/Refresh.py # this is the main, important, command to run
import Physique
import sys
sys.executable # Check which Python you are running in case you have ImportError's
print(dir(Physique))
Explanation: Physique
Mini Table of Contents
Create or refresh data files
Using Physique from a working directory not containing Physique itself
NIST Fundamental Constants
NIST Official Conversions (to metric) 
Webscraping example: JPL Solar System Dynamics (JPL SSD) - Planets and Pluto
Create or refresh data files
Create or refresh data files (if using Physique for the first time, do this first!) by running this script in the root directory of the project (i.e. ./Physique/):
python3 ./Scripts/Refresh.py
For instance, you would leave this current directory, change to the directory above (or wherever it really is) for the root directory of the project, and type the above command in the command line.
Alternatively, do it in Python here:
End of explanation
from Physique import FundamentalPhysicalConstants as FPC
print(FPC.columns)
print(FPC)
Explanation: NIST Fundamental Constants
End of explanation
g_0pd = FPC[FPC["Quantity"].str.contains("gravity") ] 
# standard acceleration of gravity as a panda DataFrame
print(g_0pd)
g_0 = g_0pd["Value"].values[0]
print(type(g_0))
print(g_0)
# access the values you're interested in 
print(g_0pd.Quantity)
print(g_0pd.Value.get_values()[0]) 
print(g_0pd.Unit.get_values()[0])
# you can also grab just the 1 entry from this DataFrame using the .loc module
FPC[FPC["Quantity"].str.contains("Boltzmann")].loc[49,:]
g_0pd.loc[303,:]
Explanation: Find a Fundamental Constant you are interested in using the usual panda modules
End of explanation
from Physique import Conversions
print(Conversions.columns)
Explanation: NIST Official Conversions (to metric)
This is the pandas DataFrame containing all the NIST Official Conversions to SI.
End of explanation
Conversions[Conversions['Toconvertfrom'].str.contains("pound-force ")]
Explanation: From the list of columns, search for the quantity you desired by trying out different search terms: e.g. I'm reading Huzel and Huang's Modern Engineering for Design of Liquid-Propellant Rocket Engines and I want to know how to convert from
* lb (pound or pound-force) for thrust into force in Newton (N)
* psia (pounds per square inch absolute) for (chamber) pressure into pressure in Pascal (Pa)
We can try to look up the U.S. or Imperial units from the Toconvertfrom column.
End of explanation
Conversions[Conversions['to'].str.contains("newton ")]
Explanation: Or we can look up the SI unit we want to convert to.
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lbf2N = Conversions.loc[340,:];
print(lbf2N)
Explanation: Look at what you want and see the index; it happens to be 340 in this example.
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print(lbf2N.Toconvertfrom)
print(lbf2N.to)
print(lbf2N.Multiplyby)
Explanation: Then the attributes can accessed by the column names.
End of explanation
print(470000 * lbf2N.Multiplyby, lbf2N.to) 
Explanation: So for example, the reusable SSME delivers a vacuum thrust of 470000 lb or
End of explanation
Conversions[Conversions['Toconvertfrom'].str.match("psi")]
Explanation: To obtain the conversion for pressure in psia, which we search for with "psi"
End of explanation
psi2Pa = Conversions.loc[372,:]
print(3028 * psi2Pa.Multiplyby, psi2Pa.to)
Explanation: So for a chamber pressure of 3028 psia for the SSME,
End of explanation
Conversions[Conversions['Toconvertfrom'].str.match("atm")]
atm2Pa = Conversions.loc[15,:]
print(3028 * psi2Pa.Multiplyby / atm2Pa.Multiplyby, atm2Pa.Toconvertfrom)
Explanation: Also, get the conversion for atmospheres (atm):
End of explanation
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