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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:
 Additional material
Step1:  <span style="color
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Python Code:
import cobra
from cobra.flux_analysis import pfba
import pandas as pd # for nice tables
pd.set_option('display.max_colwidth', -1)
from utils import show_map
import escher
map_loc = './maps/e_coli_core.Core metabolism.json' # the escher map used below
from IPython.core.interactiveshell import InteractiveShell
InteractiveShell.ast_node_interactivity = "all"
M = cobra.io.load_json_model('models/e_coli_core.json')
model = M.copy() # this way we can edit model but leave M unaltered
Explanation: Additional material: Investigating the E. coli core metabolic map
http://doi.org/10.1128/ecosalplus.10.2.1
This notebook serves either as additional material for advanced students. Or as the basis for a student project.
<span style="color:red">Assignment:</span> Read the paper describing the e. coli core model
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b = show_map([],map_loc)
b.display_in_notebook()
sol = model.optimize()
b = show_map(sol,map_loc)
b.display_in_notebook()
Explanation: <span style="color:red">Assignment:</span> Examine the network.
End of explanation
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